diff --git a/front/App.tsx b/front/App.tsx
index e443289..2a83784 100644
--- a/front/App.tsx
+++ b/front/App.tsx
@@ -5,8 +5,10 @@ import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
 import { StatusBar } from 'react-native';
 import useThemeStorage from './src/hooks/useThemeStorage';
 import { colors } from './src/constants/colors';
-import { useBookmarkStore } from './src/store/useBookmarkStore';
+// import { useBookmarkStore } from './src/store/useBookmarkStore';
 import SplashScreen from 'react-native-splash-screen';
+import { useAuthStore } from './src/store/useAuthStore';
+import { initializeAuth } from './src/util/auth';
 
 const queryClient = new QueryClient({
   defaultOptions: {
@@ -19,16 +21,19 @@ const queryClient = new QueryClient({
   },
 });
 
-
 function App(): React.JSX.Element {
-  const {theme} = useThemeStorage();
+  const { theme } = useThemeStorage();
+  const { setLoggedIn } = useAuthStore();
 
   useEffect(() => {
-    useBookmarkStore.getState().loadBookmarks();
+    initializeAuth(setLoggedIn);
+    // 북마크 로드와 함께 인증 초기화
+    // useBookmarkStore.getState().loadBookmarks();
+
     setTimeout(() => {
       SplashScreen.hide();
     }, 500);
-  }, []);
+  }, [setLoggedIn]);
 
   return (
     <QueryClientProvider client={queryClient}>
diff --git a/front/src/navigation/RootStackNavigator.tsx b/front/src/navigation/RootStackNavigator.tsx
index 33da757..50811d0 100644
--- a/front/src/navigation/RootStackNavigator.tsx
+++ b/front/src/navigation/RootStackNavigator.tsx
@@ -5,6 +5,7 @@ import LoginScreen from '../screens/oauth/LoginScreen';
 import SelectCertificationScreen from '../screens/selectCertification/SelectCertificationScreen';
 import HomeStackNavigator, { HomeStackParamList } from './HomeStackNavigator';
 import { NavigatorScreenParams } from '@react-navigation/native';
+import { useAuthStore } from '../store/useAuthStore';
 
 export type RootStackParamList = {
   AuthHome: undefined;
@@ -16,12 +17,17 @@ export type RootStackParamList = {
 const Stack = createStackNavigator<RootStackParamList>();
 
 function RootStackNavigator() {
+  const { isLoggedIn } = useAuthStore();
+
   return (
     <Stack.Navigator screenOptions={{ headerShown: false }}>
-      <Stack.Screen name="AuthHome" component={AuthHomeScreen} />
+      {isLoggedIn ? (
+        <Stack.Screen name="HomeStack" component={HomeStackNavigator} />
+      ) : (
+        <Stack.Screen name="AuthHome" component={AuthHomeScreen} />
+      )}
       <Stack.Screen name="Login" component={LoginScreen} />
       <Stack.Screen name="SelectCertification" component={SelectCertificationScreen} />
-      <Stack.Screen name="HomeStack" component={HomeStackNavigator} />
     </Stack.Navigator>
   );
 }
diff --git a/front/src/screens/bookmark/BookmarkScreen.tsx b/front/src/screens/bookmark/BookmarkScreen.tsx
index 31317ce..a8da2a4 100644
--- a/front/src/screens/bookmark/BookmarkScreen.tsx
+++ b/front/src/screens/bookmark/BookmarkScreen.tsx
@@ -1,8 +1,7 @@
-import React from 'react';
+import React, { useState, useCallback } from 'react';
 import {View, Text, ScrollView} from 'react-native';
 import { useNavigation } from '@react-navigation/native';
 import { NativeStackNavigationProp } from '@react-navigation/native-stack';
-import { useQuery } from '@tanstack/react-query';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
 import { HomeStackParamList } from '../../navigation/HomeStackNavigator';
@@ -11,40 +10,41 @@ import { ScaledSheet } from 'react-native-size-matters';
 import { fetchGet } from '../../util/api';
 import { QuestionData } from '../components/QuestionItem';
 import { useBookmarkStore } from '../../store/useBookmarkStore';
+import { useFocusEffect } from '@react-navigation/native';
 
 function BookmarkScreen() {
   const { theme } = useThemeStore();
   const styles = styling(theme);
   const navigation = useNavigation<NativeStackNavigationProp<HomeStackParamList>>();
   const { bookmarks } = useBookmarkStore();
+  const [bookmarkQuestions, setBookmarkQuestions] = useState<QuestionData[]>([]);
   console.log(bookmarks);
 
-
-  const { data: bookmarkQuestions } = useQuery<QuestionData[]>({
-    queryKey: ['bookmarkQuestions', bookmarks],
-    queryFn: () => fetchGet('exam/book-mark/question?certificationId=1'),
-    staleTime: 0,
-    gcTime: 0,
-    // refetchOnWindowFocus: true,
-    // refetchOnMount: true,
-    // refetchOnReconnect: true,
-  });
+  // 북마크 질문들을 가져오는 함수
+  const fetchBookmarkQuestions = useCallback(async () => {
+    try {
+      const data = await fetchGet('exam/book-mark/question?certificationId=1') as QuestionData[];
+      setBookmarkQuestions(data);
+    } catch (error) {
+      console.error('북마크 질문을 가져오는데 실패했습니다:', error);
+      setBookmarkQuestions([]);
+    }
+  }, []);
 
   const handleQuestionSelect = (index: number) => {
     // 네비게이션을 사용하여 QuestionPager 화면으로 이동
     navigation.navigate('QuestionPager', {
       questions: bookmarkQuestions,
       currentPage: index + 1,
-      handlePageChange: (page: number) => console.log('페이지 변경:', page),
       mode: 'bookmark',
     });
   };
 
-  // useFocusEffect(
-  //   React.useCallback(() => {
-  //     refetch();
-  //   }, [refetch])
-  // );
+  useFocusEffect(
+    React.useCallback(() => {
+      fetchBookmarkQuestions();
+    }, [fetchBookmarkQuestions])
+  );
   console.log(bookmarkQuestions);
 
   return (
diff --git a/front/src/screens/components/Header.tsx b/front/src/screens/components/Header.tsx
index bbb2b4f..55a8256 100644
--- a/front/src/screens/components/Header.tsx
+++ b/front/src/screens/components/Header.tsx
@@ -6,9 +6,9 @@ import { useNavigation } from '@react-navigation/native';
 import { StackNavigationProp } from '@react-navigation/stack';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
-import { getEncryptStorage, UserKey } from '../../util/encryptStorage';
+import { getEncryptStorage, UserNameKey } from '../../util/encryptStorage';
 import { RootStackParamList } from '../../navigation/RootStackNavigator';
-
+import { useAuthStore } from '../../store/useAuthStore';
 
 function Header() {
   const { theme } = useThemeStore(); // 현재 테마 가져오기
@@ -16,13 +16,14 @@ function Header() {
   const styles = styling(theme, insets); // 테마별 스타일 적용
   const [userName, setUserName] = useState<string | null>(null); // 사용자 이름을 저장할 상태 변수
   const navigation = useNavigation<StackNavigationProp<RootStackParamList>>();
+  const { isLoggedIn } = useAuthStore();
 
   async function fetchUserName() {
     try {
-      const data = await getEncryptStorage(UserKey);
+      const data = await getEncryptStorage(UserNameKey);
 
-      if (data && data.username) {
-        const originalName = data.username;
+      if (data) {
+        const originalName = data;
         // '_'가 포함되어 있는지 확인하고, 포함되어 있다면 '_' 앞부분만 사용
         const processedName = originalName.includes('_')
           ? originalName.split('_')[0]
@@ -38,7 +39,7 @@ function Header() {
 
   useEffect(() => {
     fetchUserName();
-  }, []);
+  }, [isLoggedIn]);
 
   const backToLoginScreen = () => {
     navigation.reset({
diff --git a/front/src/screens/components/QuestionItem.tsx b/front/src/screens/components/QuestionItem.tsx
index 2a1bf11..49de2e7 100644
--- a/front/src/screens/components/QuestionItem.tsx
+++ b/front/src/screens/components/QuestionItem.tsx
@@ -6,7 +6,7 @@ import FontAwesomeIcons from 'react-native-vector-icons/FontAwesome';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
 import { extractChoiceNumber, parseContent } from '../../constants/examParser';
-import { fetchPatch, fetchPost } from '../../util/api';
+import { fetchPost, fetchDelete } from '../../util/api';
 import ChoiceItem from './ChoiceItem';
 import { UserAnswer } from '../../screens/components/QuestionPagerScreen';
 import { useBookmarkStore } from '../../store/useBookmarkStore';
@@ -91,23 +91,24 @@ const QuestionItem = React.memo(({
     }
   };
 
-  const bookmarks = useBookmarkStore((state) => state.bookmarks);
-  const toggleBookmark = useBookmarkStore((state) => state.toggleBookmark);
   const [loading, setLoading] = useState(false);
 
+  const bookmarks = useBookmarkStore((state) => state.bookmarks);
   const isBookmarked = bookmarks.includes(question.questionId);
 
   const handleStarPress = async () => {
     if (loading) {return;}
     setLoading(true);
     try {
-      // 서버에 patch 요청
-      await fetchPatch(`exam/book-mark?questionId=${question.questionId}`);
-      // zustand 상태만 변경 (EncryptedStorage 저장은 store 내부에서 처리)
-      console.log(question.questionId);
-      toggleBookmark(question.questionId);
+      if (isBookmarked) {
+        // 북마크 제거 - DELETE 요청
+        await fetchDelete('exam/book-mark', { questionId: question.questionId });
+      } else {
+        // 북마크 추가 - POST 요청
+        await fetchPost('exam/book-mark', { questionId: question.questionId });
+      }
     } catch (e) {
-      Alert.alert('알림', '북마크를 추가할 수 없습니다.');
+      Alert.alert('알림', '북마크 처리에 실패했습니다.');
     } finally {
       setLoading(false);
     }
diff --git a/front/src/screens/myPage/MyPageScreen.tsx b/front/src/screens/myPage/MyPageScreen.tsx
index 3cd40ea..c4af4d0 100644
--- a/front/src/screens/myPage/MyPageScreen.tsx
+++ b/front/src/screens/myPage/MyPageScreen.tsx
@@ -2,49 +2,52 @@ import React, { useState } from 'react';
 import { View, Text, Pressable, Alert } from 'react-native';
 import { ScaledSheet } from 'react-native-size-matters';
 import { useMutation } from '@tanstack/react-query';
-import { useNavigation } from '@react-navigation/native';
-import { NativeStackNavigationProp } from '@react-navigation/native-stack';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
 import { fetchPost, fetchDelete } from '../../util/api';
-import { RootStackParamList } from '../../navigation/RootStackNavigator';
-import { removeEncryptStorage, JwtKey, UserKey } from '../../util/encryptStorage';
+import { removeEncryptStorage, AccessKey, UserNameKey, UserNicknameKey, CertificationKey } from '../../util/encryptStorage';
 import ThemeModal from './components/ThemeModal';
+import { useAuthStore } from '../../store/useAuthStore';
 
 type FetchMethod = typeof fetchPost | typeof fetchDelete;
 
 type ApiRequest = {
   url: string;
   method: FetchMethod;
+  data?: any;
 };
 
-interface MyPageScreenProps {
-
-}
-
-function MyPageScreen({}: MyPageScreenProps) {
+function MyPageScreen() {
   const { theme } = useThemeStore();
   const styles = styling(theme);
-  const navigation = useNavigation<NativeStackNavigationProp<RootStackParamList>>();
   const [isModalVisible, setIsModalVisible] = useState(false);
+  const { setLoggedIn, isLoggedIn } = useAuthStore();
 
   const apiMutation = useMutation({
     mutationFn: (request: ApiRequest) => {
-      return request.method(request.url, {});
+      return request.method(request.url, request.data);
     },
     onSuccess: () => {
-      removeEncryptStorage(JwtKey);
-      removeEncryptStorage(UserKey);
-      navigation.reset({
-        index: 0,
-        routes: [{ name: 'AuthHome' }],
-      });
+      // 저장소에서 데이터 제거
+      removeEncryptStorage(AccessKey);
+      removeEncryptStorage(UserNameKey);
+      removeEncryptStorage(UserNicknameKey);
+      removeEncryptStorage(CertificationKey);
+
+      // 로그인 상태 변경 (이렇게 하면 RootStackNavigator가 자동으로 AuthHome을 렌더링)
+      setLoggedIn(false);
     },
-    onError: () => {
+    onError: (error) => {
+      console.log('로그아웃 실패', error);
     },
   });
 
   const onLogout = () => {
+    if (!isLoggedIn) {
+      Alert.alert('알림', '로그인 상태가 아닙니다');
+      return;
+    }
+
     Alert.alert('로그아웃', '로그아웃하시겠습니까?', [
       {
         text: '아니오',
@@ -54,13 +57,19 @@ function MyPageScreen({}: MyPageScreenProps) {
       {
         text: '예',
         onPress: () => {
-          apiMutation.mutate({ url: 'user/logout', method: fetchPost });
+          // 빈 객체라도 body로 전송
+          apiMutation.mutate({ url: 'user/logout', method: fetchPost, data: {} });
         },
       },
     ]);
   };
 
   const onDelete = () => {
+    if (!isLoggedIn) {
+      Alert.alert('알림', '로그인 상태가 아닙니다');
+      return;
+    }
+
     Alert.alert('회원 탈퇴', '정말로 회원을 탈퇴하시겠습니까?', [
       {
         text: '아니오',
diff --git a/front/src/screens/oauth/AuthHomeScreen.tsx b/front/src/screens/oauth/AuthHomeScreen.tsx
index 79e29e5..f9fa9c3 100644
--- a/front/src/screens/oauth/AuthHomeScreen.tsx
+++ b/front/src/screens/oauth/AuthHomeScreen.tsx
@@ -10,14 +10,16 @@ import SelectCertificationScreen from '../selectCertification/SelectCertificatio
 import { useNavigation } from '@react-navigation/native';
 import { NativeStackNavigationProp } from '@react-navigation/native-stack';
 import { RootStackParamList } from '../../navigation/RootStackNavigator';
-import { getEncryptStorage, JwtKey } from '../../util/encryptStorage';
+import { AccessKey, getEncryptStorage } from '../../util/encryptStorage';
+import { useAuthStore } from '../../store/useAuthStore';
 
 export interface LoginUserResponse {
   token: string;
+  refresh: string;
   user: {
     nickname: string;
-    userId: number;
-    userName: string;
+    provider: string;
+    username: string;
   }
 }
 
@@ -26,27 +28,24 @@ function AuthHomeScreen() {
   const insets = useSafeAreaInsets();
   const styles = styling(theme, insets);
   const [currentPage, setCurrentPage] = useState(0);
+  const { isLoggedIn } = useAuthStore();
 
   const navigation = useNavigation<NativeStackNavigationProp<RootStackParamList, 'Login'>>();
 
   useEffect(() => {
     const checkJwt = async () => {
-      try {
-        const jwt = await getEncryptStorage(JwtKey);
-        if (jwt) {
-          // 토큰이 있으면 바로 홈 화면으로 이동
-          // certifications 요청은 해당 화면에서 자동으로 이루어짐
-          navigation.navigate('HomeStack');
-          // certifications 요청이 실패하면 해당 화면의 오류 처리에서
-          // 토큰 관련 오류 처리가 자동으로 이루어질 것임
-        }
-      } catch (error) {
-        console.error('토큰 확인 오류:', error);
+      if (!isLoggedIn) {
+        return; // 로그아웃 상태면 체크하지 않음
+      }
+
+      const jwt = await getEncryptStorage(AccessKey);
+      if (jwt) {
+        navigation.navigate('HomeStack');
       }
     };
 
     checkJwt();
-  }, [navigation]);
+  }, [navigation, isLoggedIn]);
 
   const handleLoginSuccess = useCallback(() => {
     setCurrentPage(1);
diff --git a/front/src/screens/oauth/GoogleLogin.tsx b/front/src/screens/oauth/GoogleLogin.tsx
index 39f9e0b..af31cdb 100644
--- a/front/src/screens/oauth/GoogleLogin.tsx
+++ b/front/src/screens/oauth/GoogleLogin.tsx
@@ -1,19 +1,20 @@
-import React from 'react';
-import { Text, Pressable } from 'react-native';
+import React, { useState } from 'react';
+import { Text, Pressable, Alert, View } from 'react-native';
 import { ScaledSheet } from 'react-native-size-matters';
 import { useMutation } from '@tanstack/react-query';
 import { GoogleSignin } from '@react-native-google-signin/google-signin';
-import { setEncryptStorage, JwtKey, UserKey } from '../../util/encryptStorage';
+import { setEncryptStorage, AccessKey, UserNameKey, UserProviderKey } from '../../util/encryptStorage';
 import Config from 'react-native-config';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
 import { fetchPost } from '../../util/api';
 import { LoginUserResponse } from './AuthHomeScreen';
+import { useAuthStore } from '../../store/useAuthStore';
 
 GoogleSignin.configure({
   webClientId: Config.WEB_CLIENT_ID,
   iosClientId: Config.IOS_CLIENT_ID,
-  offlineAccess: false,
+  offlineAccess: true,
 });
 
 type GoogleLoginProps = {
@@ -32,6 +33,8 @@ function GoogleLogin(
 ) {
   const {theme} = useThemeStore();
   const styles = styling(theme);
+  const { setLoggedIn } = useAuthStore();
+  const [log, setLog] = useState('');
 
     // 구글 로그인 정보를 백엔드로 전송하는 mutation
     const { mutate: sendTokensToBackend } = useMutation<LoginUserResponse, Error, GoogleLoginResponse>({
@@ -43,15 +46,19 @@ function GoogleLogin(
         return result;
       },
       onSuccess: async (data) => {
-        console.log('구글 로그인 성공');
-        if (data.token) {
-          await setEncryptStorage(JwtKey, data.token);
-          await setEncryptStorage(UserKey, data.user);
-          onLoginSuccess?.();
-        }
+        console.log('구글 백엔드 서버 요청 성공');
+        console.log(data);
+        setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '구글 백엔드 서버 요청 성공');
+        await setEncryptStorage(AccessKey, data.token);
+        await setEncryptStorage(UserNameKey, data.user.username);
+        await setEncryptStorage(UserProviderKey, data.user.provider);
+        setLoggedIn(true);
+        onLoginSuccess?.();
       },
-      onError: () => {
-        console.log('구글 로그인 실패');
+      onError: (data) => {
+        console.log('구글 백엔드 서버 요청 실패');
+        console.log(data);
+        setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '구글 백엔드 서버 요청 실패' + data);
       },
     });
 
@@ -59,24 +66,29 @@ function GoogleLogin(
   const { mutate: handleGoogleLogin } = useMutation<GoogleLoginResponse, Error>({
     mutationFn: async () => {
       await GoogleSignin.hasPlayServices();
-      const userInfo = await GoogleSignin.signIn();
+      await GoogleSignin.signIn();
       const tokens = await GoogleSignin.getTokens();
 
       return {
-        userInfo,
         tokens,
       };
     },
-    onSuccess: (loginData) => {
-      console.log('구글 로그인 성공');
-      sendTokensToBackend(loginData);
+    onSuccess: (tokens) => {
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '구글 서버 요청 성공');
+      sendTokensToBackend(tokens);
+      console.log(tokens);
+      console.log(tokens.tokens.accessToken);
     },
-    onError: () => {
-      console.log('구글 로그인 실패');
+    onError: (data) => {
+      console.log('구글 서버 요청 실패');
+      console.log(data);
+      Alert.alert('구글 로그인 실패', '다시 시도해주세요');
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '구글 서버 요청 실패' + data);
     },
   });
 
   return (
+    <View>
    <Pressable
       style={({pressed}) => [
         styles.button,
@@ -86,11 +98,17 @@ function GoogleLogin(
     >
       <Text style={styles.buttonText}>구글 계정으로 계속하기</Text>
     </Pressable>
+      <Text>{log}</Text>
+    </View>
   );
 }
 
 const styling = (theme: themeMode) => ScaledSheet.create({
-
+  buttonContainer: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
   button: {
     width: '100%',
     padding: '15@ms0.3',
diff --git a/front/src/screens/oauth/KakaoLogin.tsx b/front/src/screens/oauth/KakaoLogin.tsx
index 6f1bd4c..da31756 100644
--- a/front/src/screens/oauth/KakaoLogin.tsx
+++ b/front/src/screens/oauth/KakaoLogin.tsx
@@ -1,13 +1,14 @@
-import React from 'react';
-import { Pressable, Text } from 'react-native';
+import React, { useState } from 'react';
+import { Alert, Pressable, Text, View } from 'react-native';
 import { ScaledSheet } from 'react-native-size-matters';
 import { login, KakaoOAuthToken } from '@react-native-seoul/kakao-login';
 import { useMutation } from '@tanstack/react-query';
-import { setEncryptStorage, JwtKey, UserKey } from '../../util/encryptStorage';
+import { setEncryptStorage, AccessKey, UserNameKey, UserProviderKey } from '../../util/encryptStorage';
 import { colors } from '../../constants/colors';
 import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { fetchPost } from '../../util/api';
 import { LoginUserResponse } from './AuthHomeScreen';
+import { useAuthStore } from '../../store/useAuthStore';
 
 interface Props {
   onLoginSuccess?: () => void;
@@ -16,7 +17,8 @@ interface Props {
 function KakaoLogin({ onLoginSuccess }: Props) {
   const {theme} = useThemeStore();
   const styles = styling(theme);
-
+  const { setLoggedIn } = useAuthStore();
+  const [log, setLog] = useState('');
 
   // 카카오 로그인 정보를 백엔드로 전송하는 mutation
   const { mutate: sendTokensToBackend } = useMutation<LoginUserResponse, Error, KakaoOAuthToken>({
@@ -28,13 +30,19 @@ function KakaoLogin({ onLoginSuccess }: Props) {
       return result;
     },
     onSuccess: async (data) => {
+      console.log(data);
+      console.log('카카오 백엔드 서버 요청 성공');
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '카카오 백엔드 서버 요청 성공');
+      await setEncryptStorage(AccessKey, data.token);
+      await setEncryptStorage(UserNameKey, data.user.username);
+      await setEncryptStorage(UserProviderKey, data.user.provider);
+      setLoggedIn(true);
       onLoginSuccess?.();
-
-      if (data.token) {
-        console.log('Login successful:', data);
-        await setEncryptStorage(JwtKey, data.token);
-        await setEncryptStorage(UserKey, data.user);
-      }
+    },
+    onError: (data) => {
+      console.log('카카오 백엔드 서버 요청 실패');
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '카카오 백엔드 서버 요청 실패' + data);
+      Alert.alert('카카오 로그인 실패', '다시 시도해주세요');
     },
   });
 
@@ -45,21 +53,29 @@ function KakaoLogin({ onLoginSuccess }: Props) {
       return token;
     },
     onSuccess: (loginData) => {
+      console.log('카카오 서버 요청 성공');
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '카카오 서버 요청 성공');
       sendTokensToBackend(loginData);
     },
+    onError: (data) => {
+      console.log('카카오 서버 요청 실패');
+      setLog(prevLog => prevLog + (prevLog ? '\n' : '') + '카카오 서버 요청 실패' + data);
+    },
   });
 
-
   return (
-    <Pressable
-      style={({pressed}) => [
-        styles.button,
-        pressed && styles.buttonPressed,
-      ]}
-      onPress={() => handleKakaoLogin()}
-    >
-      <Text style={styles.buttonText}>카카오 계정으로 계속하기</Text>
-    </Pressable>
+    <View>
+      <Pressable
+        style={({pressed}) => [
+          styles.button,
+          pressed && styles.buttonPressed,
+        ]}
+        onPress={() => handleKakaoLogin()}
+      >
+        <Text style={styles.buttonText}>카카오 계정으로 계속하기</Text>
+      </Pressable>
+      <Text>{log}</Text>
+    </View>
   );
 }
 
diff --git a/front/src/screens/oauth/LoginScreen.tsx b/front/src/screens/oauth/LoginScreen.tsx
index 6075917..710230f 100644
--- a/front/src/screens/oauth/LoginScreen.tsx
+++ b/front/src/screens/oauth/LoginScreen.tsx
@@ -5,7 +5,7 @@ import useThemeStore, { themeMode } from '../../store/useThemeStore';
 import { colors } from '../../constants/colors';
 import KakaoLogin from '../oauth/KakaoLogin';
 import GoogleLogin from '../oauth/GoogleLogin';
-import { removeEncryptStorage, JwtKey, UserKey } from '../../util/encryptStorage';
+import { removeEncryptStorage, AccessKey, UserNameKey, UserNicknameKey } from '../../util/encryptStorage';
 
 interface LoginPageProps {
   onLoginSuccess?: () => void;
@@ -24,8 +24,9 @@ const LoginPage: React.FC<LoginPageProps> = ({ onLoginSuccess, onNonLogin }) =>
 
   const handleNonLogin = () => {
     if (onNonLogin) {
-      removeEncryptStorage(JwtKey);
-      removeEncryptStorage(UserKey);
+      removeEncryptStorage(AccessKey);
+      removeEncryptStorage(UserNameKey);
+      removeEncryptStorage(UserNicknameKey);
       onNonLogin();
     }
   };
diff --git a/front/src/screens/selectCertification/SelectCertificationScreen.tsx b/front/src/screens/selectCertification/SelectCertificationScreen.tsx
index fef3d9a..dac1c22 100644
--- a/front/src/screens/selectCertification/SelectCertificationScreen.tsx
+++ b/front/src/screens/selectCertification/SelectCertificationScreen.tsx
@@ -10,6 +10,7 @@ import { RootStackParamList } from '../../navigation/RootStackNavigator';
 import { NativeStackScreenProps } from '@react-navigation/native-stack';
 import { useNavigation } from '@react-navigation/native';
 import useCertificationStore from '../../store/useCertificationStore';
+import { useAuthStore } from '../../store/useAuthStore';
 
 export interface Certification {
   certificationId: number;
@@ -21,6 +22,7 @@ const SelectCertificationScreen = () => {
   const insets = useSafeAreaInsets();
   const styles = styling(theme, insets);
   const navigation = useNavigation<NativeStackScreenProps<RootStackParamList, 'SelectCertification'>['navigation']>();
+  const { isLoggedIn, setLoggedIn } = useAuthStore();
 
   const [searchQuery, setSearchQuery] = useState<string>('');
   const { selectedCertifications, toggleCertification, loadCertifications } = useCertificationStore();
@@ -57,10 +59,16 @@ const SelectCertificationScreen = () => {
   };
 
   const handleComplete = () => {
-    navigation.replace('HomeStack', {
-      screen: 'MainTab',
-      params: { certifications: selectedCertifications },
-    });
+    if (isLoggedIn) {
+      // 로그인 상태: HomeStack으로 이동
+      navigation.replace('HomeStack', {
+        screen: 'MainTab',
+        params: { certifications: selectedCertifications },
+      });
+    } else {
+      // 비로그인 상태: 로그인 상태를 true로 설정 (이렇게 하면 RootStackNavigator가 HomeStack을 렌더링)
+      setLoggedIn(true);
+    }
   };
 
   return (
diff --git a/front/src/screens/wrongQuestion/WrongQuestionScreen.tsx b/front/src/screens/wrongQuestion/WrongQuestionScreen.tsx
index 2c3971c..8b3567b 100644
--- a/front/src/screens/wrongQuestion/WrongQuestionScreen.tsx
+++ b/front/src/screens/wrongQuestion/WrongQuestionScreen.tsx
@@ -10,30 +10,30 @@ import { QuestionData } from '../components/QuestionItem';
 import { useNavigation } from '@react-navigation/native';
 import { NativeStackNavigationProp } from '@react-navigation/native-stack';
 import { HomeStackParamList } from '../../navigation/HomeStackNavigator';
+import { useFocusEffect } from '@react-navigation/native';
 
 const WrongQuestionScreen = () => {
   const { theme } = useThemeStore();
   const styles = styling(theme);
   const navigation = useNavigation<NativeStackNavigationProp<HomeStackParamList>>();
 
-  const { data: wrongQuestions } = useQuery<QuestionData[]>({
+  const { data: wrongQuestions, refetch } = useQuery<QuestionData[]>({
     queryKey: ['wrongQuestions'],
-    queryFn: () => {
-      console.log('wrongQuestions fetch');
-      return fetchGet('exam/wrong-questions?status=WRONG');
-    },
-    staleTime: 0,
-    gcTime: 0,
-
+    queryFn: () => fetchGet('exam/wrong-questions?status=WRONG'),
   });
 
+  useFocusEffect(
+    React.useCallback(() => {
+      refetch();
+    }, [refetch])
+  );
   console.log(wrongQuestions);
+
   // 문제 클릭 핸들러
   const handleQuestionSelect = (index: number) => {
     navigation.navigate('QuestionPager', {
       questions: wrongQuestions,
       currentPage: index + 1,
-      handlePageChange: (page: number) => console.log('페이지 변경:', page),
       mode: 'wrongQuestion',
     });
   };
diff --git a/front/src/store/useAuthStore.ts b/front/src/store/useAuthStore.ts
new file mode 100644
index 0000000..89663fa
--- /dev/null
+++ b/front/src/store/useAuthStore.ts
@@ -0,0 +1,11 @@
+import { create } from 'zustand';
+
+interface AuthState {
+  isLoggedIn: boolean;
+  setLoggedIn: (status: boolean) => void;
+}
+
+export const useAuthStore = create<AuthState>((set) => ({
+  isLoggedIn: false,
+  setLoggedIn: (status) => set({ isLoggedIn: status }),
+}));
diff --git a/front/src/store/useBookmarkStore.ts b/front/src/store/useBookmarkStore.ts
index 67a2b88..765e1ad 100644
--- a/front/src/store/useBookmarkStore.ts
+++ b/front/src/store/useBookmarkStore.ts
@@ -1,46 +1,46 @@
 // store/useBookmarkStore.ts
 import { create } from 'zustand';
-import { getEncryptStorage, setEncryptStorage, BookMarkKey } from '../util/encryptStorage';
+import { fetchGet } from '../util/api';
 
 interface BookmarkState {
   bookmarks: number[];
-  toggleBookmark: (id: number) => void;
-  setBookmarks: (arr: number[]) => void;
-  loadBookmarks: () => Promise<void>;
+  isLoading: boolean;
+  fetchBookmarks: (certificationId?: number) => Promise<void>;
+  addBookmarkLocally: (id: number) => void;
+  removeBookmarkLocally: (id: number) => void;
+  clearBookmarks: () => void;
 }
 
 export const useBookmarkStore = create<BookmarkState>((set) => ({
   bookmarks: [],
-  toggleBookmark: (id: number) => {
-    set((state) => {
-      const exists = state.bookmarks.includes(id);
-      const newArr = exists
-        ? state.bookmarks.filter((i) => i !== id)
-        : [...state.bookmarks, id];
-      // 상태 변경 후 EncryptedStorage에도 저장
-      setEncryptStorage(BookMarkKey, newArr);
-      console.log('newArr',newArr);
+  isLoading: false,
 
-      return { bookmarks: newArr };
-    });
+  fetchBookmarks: async (certificationId = 1) => {
+    set({ isLoading: true });
+    try {
+      const data = await fetchGet(`exam/book-mark/question?certificationId=${certificationId}`) as Array<{ questionId: number }>;
+      const bookmarkIds = data.map(item => item.questionId);
+      set({ bookmarks: bookmarkIds, isLoading: false });
+    } catch (error) {
+      console.error('북마크 목록을 가져오는데 실패했습니다:', error);
+      set({ bookmarks: [], isLoading: false });
+    }
   },
-  setBookmarks: (arr: number[]) => {
-    set({ bookmarks: arr });
-    setEncryptStorage(BookMarkKey, arr);
+
+  // 서버 요청 성공 후 로컬 상태 업데이트용
+  addBookmarkLocally: (id: number) => {
+    set((state) => ({
+      bookmarks: state.bookmarks.includes(id) ? state.bookmarks : [...state.bookmarks, id],
+    }));
   },
-  loadBookmarks: async () => {
-    const raw = await getEncryptStorage(BookMarkKey);
-    if (raw) {
-      try {
-        const parsed = JSON.parse(raw);
-        if (Array.isArray(parsed)) {set({ bookmarks: parsed });}
-        else if (typeof parsed === 'number') {set({ bookmarks: [parsed] });}
-        else {set({ bookmarks: [] });}
-      } catch {
-        set({ bookmarks: [] });
-      }
-    } else {
-      set({ bookmarks: [] });
-    }
+
+  removeBookmarkLocally: (id: number) => {
+    set((state) => ({
+      bookmarks: state.bookmarks.filter(bookmarkId => bookmarkId !== id),
+    }));
+  },
+
+  clearBookmarks: () => {
+    set({ bookmarks: [] });
   },
 }));
diff --git a/front/src/util/api.ts b/front/src/util/api.ts
index 48c4f5a..d3067e8 100644
--- a/front/src/util/api.ts
+++ b/front/src/util/api.ts
@@ -1,47 +1,6 @@
-import { getEncryptStorage, JwtKey } from '../util/encryptStorage';
+import { fetchWithAutoRefresh } from './auth';
 import Config from 'react-native-config';
 
-// 헤더 생성 함수 - 토큰이 있으면 포함, 없으면 기본 헤더만 반환
-const createHeaders = async (): Promise<Headers> => {
-  const headers = new Headers({
-    'Content-Type': 'application/json',
-  });
-
-  try {
-    const token = await getEncryptStorage(JwtKey);
-    if (token) {
-      headers.append('Authorization', token);
-    }
-  } catch (error) {
-    console.log('토큰이 없거나 가져오는 중 오류 발생');
-  }
-
-  return headers;
-};
-
-type FetchOptions = RequestInit & { retryOn401?: boolean };
-
-export async function fetchWithAutoRefresh(
-  url: string,
-  options: FetchOptions = {},
-  createHeadersFn = createHeaders
-): Promise<Response> {
-  const { retryOn401, ...fetchOptions } = options; // retryOn401만 분리
-  let headers = await createHeadersFn();
-  let response = await fetch(url, { ...fetchOptions, headers });
-
-  if (response.status === 401 && retryOn401 !== false) {
-    const newToken = await getEncryptStorage(JwtKey);
-    if (newToken) {
-      headers = await createHeadersFn();
-      response = await fetch(url, { ...fetchOptions, headers });
-    } else {
-      throw new Error('토큰 재발급 실패');
-    }
-  }
-  return response;
-}
-
 // GET 요청
 export const fetchGet = async <T>(endpoint: string): Promise<T> => {
   const url = `${Config.BASE_URL}${endpoint}`;
@@ -52,11 +11,8 @@ export const fetchGet = async <T>(endpoint: string): Promise<T> => {
 
 // POST 요청
 export const fetchPost = async <T>(endpoint: string, data?: any): Promise<T | null> => {
-  const headers = await createHeaders();
-
   const options: RequestInit = {
     method: 'POST',
-    headers,
     credentials: 'include',
   };
 
@@ -64,12 +20,11 @@ export const fetchPost = async <T>(endpoint: string, data?: any): Promise<T | nu
     options.body = JSON.stringify(data);
   }
 
-  const response = await fetch(`${Config.BASE_URL}${endpoint}`, options);
+  const response = await fetchWithAutoRefresh(`${Config.BASE_URL}${endpoint}`, options);
 
   if (!response.ok) {
     console.log(response);
     throw new Error(`HTTP error! Status: ${response.status}`);
-
   }
 
   // 200이지만 body가 비어 있을 수 있으므로 예외 처리
@@ -83,11 +38,8 @@ export const fetchPost = async <T>(endpoint: string, data?: any): Promise<T | nu
 
 // PATCH 요청
 export const fetchPatch = async <T>(endpoint: string, data?: any): Promise<T | null> => {
-  const headers = await createHeaders();
-
   const options: RequestInit = {
     method: 'PATCH',
-    headers,
     credentials: 'include',
   };
 
@@ -95,7 +47,7 @@ export const fetchPatch = async <T>(endpoint: string, data?: any): Promise<T | n
     options.body = JSON.stringify(data);
   }
 
-  const response = await fetch(`${Config.BASE_URL}${endpoint}`, options);
+  const response = await fetchWithAutoRefresh(`${Config.BASE_URL}${endpoint}`, options);
 
   if (!response.ok) {
     throw new Error(`HTTP error! Status: ${response.status}`);
@@ -112,12 +64,8 @@ export const fetchPatch = async <T>(endpoint: string, data?: any): Promise<T | n
 
 // PUT 요청
 export const fetchPut = async <T>(endpoint: string, data: any): Promise<T> => {
-  const headers = await createHeaders();
-
-
-  const response = await fetch(`${Config.BASE_URL}${endpoint}`, {
+  const response = await fetchWithAutoRefresh(`${Config.BASE_URL}${endpoint}`, {
     method: 'PUT',
-    headers,
     credentials: 'include',
     body: JSON.stringify(data),
   });
@@ -131,12 +79,8 @@ export const fetchPut = async <T>(endpoint: string, data: any): Promise<T> => {
 
 // DELETE 요청
 export const fetchDelete = async <T>(endpoint: string, data?: any): Promise<T> => {
-  const headers = await createHeaders();
-
-
   const options: RequestInit = {
     method: 'DELETE',
-    headers,
     credentials: 'include',
   };
 
@@ -144,7 +88,7 @@ export const fetchDelete = async <T>(endpoint: string, data?: any): Promise<T> =
     options.body = JSON.stringify(data);
   }
 
-  const response = await fetch(`${Config.BASE_URL}${endpoint}`, options);
+  const response = await fetchWithAutoRefresh(`${Config.BASE_URL}${endpoint}`, options);
 
   if (!response.ok) {
     throw new Error(`HTTP error! Status: ${response.status}`);
@@ -155,11 +99,8 @@ export const fetchDelete = async <T>(endpoint: string, data?: any): Promise<T> =
 
 // POST 요청
 export const fetchGPTPost = async <T>(endpoint: string, data?: any): Promise<T | null> => {
-  const headers = await createHeaders();
-
   const options: RequestInit = {
     method: 'POST',
-    headers,
     credentials: 'include',
   };
 
@@ -167,7 +108,7 @@ export const fetchGPTPost = async <T>(endpoint: string, data?: any): Promise<T |
     options.body = JSON.stringify(data);
   }
 
-  const response = await fetch(`${Config.GPT_BASE_URL}${endpoint}`, options);
+  const response = await fetchWithAutoRefresh(`${Config.GPT_BASE_URL}${endpoint}`, options);
 
   if (!response.ok) {
     throw new Error(`HTTP error! Status: ${response.status}`);
diff --git a/front/src/util/auth.ts b/front/src/util/auth.ts
new file mode 100644
index 0000000..abac7a9
--- /dev/null
+++ b/front/src/util/auth.ts
@@ -0,0 +1,139 @@
+import { getEncryptStorage, AccessKey, setEncryptStorage, UserNameKey, UserNicknameKey, removeEncryptStorage } from './encryptStorage';
+import Config from 'react-native-config';
+
+export const initializeAuth = async (setLoggedIn: (loggedIn: boolean) => void) => {
+  try {
+    console.log('앱 시작 - 토큰 확인 중...');
+    const token = await getEncryptStorage(AccessKey);
+
+    if (token) {
+      console.log('저장된 토큰 발견 - 자동 로그인');
+      setLoggedIn(true);
+    } else {
+      console.log('토큰 없음 - 로그인 필요');
+      setLoggedIn(false);
+    }
+  } catch (error) {
+    console.error('인증 초기화 실패:', error);
+    setLoggedIn(false);
+  }
+};
+
+// 헤더 생성 함수 - 사전 토큰 갱신 포함
+export const createHeaders = async (): Promise<Headers> => {
+  const headers = new Headers({
+    'Content-Type': 'application/json',
+  });
+
+  try {
+    const token = await ensureValidToken(); // 🔄 사전 갱신 로직
+    if (token) {
+      headers.append('Authorization', `${token}`);
+      console.log('Authorization', `${token}`);
+    }
+  } catch (error) {
+    console.log('토큰 처리 중 오류 발생:', error);
+  }
+
+  return headers;
+};
+
+type FetchOptions = RequestInit & { retryOn401?: boolean };
+
+// 리프레시 토큰으로 새 액세스 토큰 발급받는 함수
+export const refreshAccessToken = async (): Promise<string | null> => {
+  try {
+    const username = await getEncryptStorage(UserNameKey);
+    if (!username) {
+      return null;
+    }
+
+    const response = await fetch(`${Config.BASE_URL}/refresh`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        username,
+      }),
+    });
+
+    if (response.ok) {
+      const { accessToken } = await response.json();
+      await setEncryptStorage(AccessKey, accessToken); // 새 토큰 저장
+      return accessToken;
+    } else {
+      // 토큰 갱신 실패 시 로컬 데이터 정리
+      await removeEncryptStorage(AccessKey);
+      await removeEncryptStorage(UserNameKey);
+      await removeEncryptStorage(UserNicknameKey);
+      return null;
+    }
+
+  } catch (error) {
+    console.error('토큰 리프레시 실패:', error);
+    return null;
+  }
+};
+
+// JWT 토큰 디코딩해서 만료 시간 확인
+const isTokenExpiringSoon = (token: string, bufferMinutes: number = 5): boolean => {
+  try {
+    // Bearer 접두사 제거 후 JWT 디코딩
+    const cleanToken = token.replace(/^Bearer\s+/, '');
+    const payload = JSON.parse(atob(cleanToken.split('.')[1]));
+    const currentTime = Math.floor(Date.now() / 1000); // 현재 시간 (초)
+    const expirationTime = payload.exp; // 토큰 만료 시간 (초)
+
+    // 만료 시간 - 버퍼 시간(기본 5분) 전에 갱신
+    return (expirationTime - currentTime) < (bufferMinutes * 60);
+  } catch (error) {
+    console.error('토큰 파싱 실패:', error);
+    return true; // 파싱 실패 시 갱신 필요로 간주
+  }
+};
+
+// 토큰 사전 갱신 함수
+const ensureValidToken = async (): Promise<string | null> => {
+  try {
+    const currentToken = await getEncryptStorage(AccessKey);
+
+    if (!currentToken) {
+      return null; // 토큰이 없으면 로그인 필요
+    }
+
+    // 토큰이 곧 만료되는지 확인 (5분 전에 미리 갱신)
+    if (isTokenExpiringSoon(currentToken, 5)) {
+      console.log('토큰이 곧 만료됩니다. 사전 갱신을 시도합니다.');
+      const newToken = await refreshAccessToken();
+      return newToken || currentToken; // 갱신 실패 시 기존 토큰 사용
+    }
+
+    return currentToken; // 아직 유효한 토큰
+  } catch (error) {
+    console.error('토큰 확인 실패:', error);
+    return null;
+  }
+};
+
+// fetchWithAutoRefresh 수정
+export async function fetchWithAutoRefresh(
+  url: string,
+  options: FetchOptions = {},
+  createHeadersFn = createHeaders
+): Promise<Response> {
+  const { retryOn401, ...fetchOptions } = options;
+  let headers = await createHeadersFn(); // 이미 사전 갱신 완료
+  let response = await fetch(url, { ...fetchOptions, headers });
+
+  // 그래도 401이 발생하면 한 번 더 시도 (fallback)
+  if (response.status === 401 && retryOn401 !== false) {
+    console.log('사전 갱신에도 불구하고 401 발생, 추가 갱신 시도');
+    const newAccessToken = await refreshAccessToken();
+    if (newAccessToken) {
+      headers = await createHeadersFn();
+      response = await fetch(url, { ...fetchOptions, headers });
+    } else {
+      throw new Error('토큰 재발급 실패 - 로그인이 필요합니다');
+    }
+  }
+  return response;
+}
diff --git a/front/src/util/encryptStorage.ts b/front/src/util/encryptStorage.ts
index c4c4b7d..20b9bb6 100644
--- a/front/src/util/encryptStorage.ts
+++ b/front/src/util/encryptStorage.ts
@@ -1,7 +1,9 @@
 import EncryptedStorage from 'react-native-encrypted-storage';
 
-const JwtKey = 'user_jwt';
-const UserKey = 'user';
+const AccessKey = 'access_token';
+const UserNameKey = 'user_name';
+const UserProviderKey = 'user_provider';
+const UserNicknameKey = 'user_nickname';
 const CertificationKey = 'certification';
 const BookMarkKey = 'bookmarks';
 
@@ -23,4 +25,4 @@ const removeEncryptStorage = async ( key: string) => {
   }
 };
 
-export {setEncryptStorage, getEncryptStorage, removeEncryptStorage, JwtKey, UserKey, CertificationKey, BookMarkKey};
+export {setEncryptStorage, getEncryptStorage, removeEncryptStorage, AccessKey, UserNameKey, UserProviderKey, UserNicknameKey, CertificationKey, BookMarkKey };