diff --git a/src/entities/chat/model/socket.ts b/src/entities/chat/model/socket.ts
index 48148638..702de261 100644
--- a/src/entities/chat/model/socket.ts
+++ b/src/entities/chat/model/socket.ts
@@ -1,5 +1,7 @@
+import { error } from "console";
 import { MessageProps } from "./types";
 import { useAuthStore } from "@/features/auth/model/auth.store";
+import { refreshAccessToken } from "@/shared/api/refresh";
 
 export interface ChatSocketEvents {
   onOpen?: () => void;
@@ -64,7 +66,13 @@ export class ChatSocket {
         }
       };
 
-      this.socket.onclose = (event) => {
+      this.socket.onclose = async (event) => {
+        if (event.code === 4001) {
+          console.warn("[Socket] Token expired (4001)");
+
+          const newToken = await refreshAccessToken();
+          this.reconnect();
+        }
         console.warn("[Socket] Closed:", event.code);
         this.events.onClose?.(event.code, event.reason);
         this.socket = null;
@@ -78,6 +86,12 @@ export class ChatSocket {
     });
   }
 
+  private reconnect() {
+    console.log("[Socket] Reconnecting after refresh…");
+    this.socket = null;
+    this.connect();
+  }
+
   sendMessage(type: "text" | "image", content: string) {
     if (!this.socket || this.socket.readyState !== WebSocket.OPEN) {
       console.warn("[Socket] Not connected");
diff --git a/src/features/auth/ui/LoginForm/LoginForm.tsx b/src/features/auth/ui/LoginForm/LoginForm.tsx
index 31772976..b2810fb6 100644
--- a/src/features/auth/ui/LoginForm/LoginForm.tsx
+++ b/src/features/auth/ui/LoginForm/LoginForm.tsx
@@ -39,6 +39,7 @@ export const LoginForm = ({
       }>("/auth/login", {
         method: "POST",
         body: JSON.stringify({ email, password }),
+        noAuth: true,
       });
 
       setAccessToken(res.accessToken);
diff --git a/src/features/auth/ui/SignUpForm/SignUpForm.tsx b/src/features/auth/ui/SignUpForm/SignUpForm.tsx
index b49bfab5..3a349e3c 100644
--- a/src/features/auth/ui/SignUpForm/SignUpForm.tsx
+++ b/src/features/auth/ui/SignUpForm/SignUpForm.tsx
@@ -135,6 +135,7 @@ export const SignUpForm = ({ onSuccess, onError }: SignUpFormProps) => {
       const res = await apiFetch("/api/users/", {
         method: "POST",
         body: JSON.stringify(body),
+        noAuth: true,
       });
 
       console.log("회원가입 성공:", res);
diff --git a/src/shared/api/fetcher.ts b/src/shared/api/fetcher.ts
index ca387a0b..47632c48 100644
--- a/src/shared/api/fetcher.ts
+++ b/src/shared/api/fetcher.ts
@@ -1,19 +1,26 @@
+import { useAuthStore } from "@/features/auth/model/auth.store";
+import { refreshAccessToken } from "./refresh";
 import { useModalStore } from "@/shared/model/modal.store";
 
 const BASE_URL = process.env.NEXT_PUBLIC_API_URL;
 
 export async function apiFetch<T>(
   endpoint: string,
-  options: RequestInit,
+  options: RequestInit & { noAuth?: boolean },
 ): Promise<T> {
-  const { headers, ...restOptions } = options;
+  const { headers, noAuth, ...restOptions } = options;
+  const { accessToken, setAccessToken, logout } = useAuthStore.getState();
   const { openModal, closeModal } = useModalStore.getState();
 
   const defaultHeaders: HeadersInit = {
     "Content-Type": "application/json",
   };
 
-  const res = await fetch(`${BASE_URL}${endpoint}`, {
+  if (!noAuth && typeof window !== "undefined") {
+    defaultHeaders["Authorization"] = `Bearer ${accessToken}`;
+  }
+
+  let res = await fetch(`${BASE_URL}${endpoint}`, {
     headers: { ...defaultHeaders, ...headers },
     cache: "no-store",
     credentials: "include",
@@ -21,14 +28,19 @@ export async function apiFetch<T>(
   });
 
   //AccessToken 만료 처리
-  if (res.status === 401) {
-    openModal("normal", {
-      message: "세션이 만료되었습니다. 다시 로그인 해주세요.",
-      buttonText: "확인",
-      onClick: () => {
-        closeModal();
-        location.replace("/login");
-      },
+  if (res.status === 401 && !noAuth) {
+    const newToken = await refreshAccessToken();
+
+    if (!newToken) throw new Error("세션 만료");
+
+    defaultHeaders["Authorization"] = `Bearer ${newToken}`;
+
+    //동일한 경로에 요청 재시도
+    res = await fetch(`${BASE_URL}${endpoint}`, {
+      headers: { ...defaultHeaders, ...headers },
+      cache: "no-store",
+      credentials: "include",
+      ...restOptions,
     });
   }
 
diff --git a/src/shared/api/refresh.ts b/src/shared/api/refresh.ts
index 804caa5b..4e3187b7 100644
--- a/src/shared/api/refresh.ts
+++ b/src/shared/api/refresh.ts
@@ -1,26 +1,48 @@
 import { useAuthStore } from "@/features/auth/model/auth.store";
+import { useModalStore } from "@/shared/model/modal.store";
 
 const BASE_URL = process.env.NEXT_PUBLIC_API_URL;
 
 export async function refreshAccessToken(): Promise<string | null> {
+  const { setAccessToken, logout } = useAuthStore.getState();
+  const { openModal, closeModal } = useModalStore.getState();
+
   try {
     const res = await fetch(`${BASE_URL}/auth/refresh`, {
       method: "POST",
-      credentials: "include", // 쿠키 전송
+      credentials: "include",
     });
 
     if (!res.ok) {
+      logout();
+      openModal("normal", {
+        message: "세션이 만료되었습니다. 다시 로그인 해주세요.",
+        buttonText: "확인",
+        onClick: () => {
+          closeModal();
+          location.replace("/login");
+        },
+      });
       return null;
     }
 
     const data = await res.json();
-    const newAccessToken = data.accessToken as string;
+    const newToken = data.accessToken as string;
+
+    setAccessToken(newToken);
 
-    // zustand 업데이트
-    useAuthStore.getState().setAccessToken(newAccessToken);
+    return newToken;
+  } catch (err) {
+    logout();
+    openModal("normal", {
+      message: "세션이 만료되었습니다. 다시 로그인 해주세요.",
+      buttonText: "확인",
+      onClick: () => {
+        closeModal();
+        location.replace("/login");
+      },
+    });
 
-    return newAccessToken;
-  } catch {
     return null;
   }
 }