diff --git a/src/main/java/com/example/springhw31/controller/UserController.java b/src/main/java/com/example/springhw31/controller/UserController.java
index 7eca68b..1f503b0 100644
--- a/src/main/java/com/example/springhw31/controller/UserController.java
+++ b/src/main/java/com/example/springhw31/controller/UserController.java
@@ -1,16 +1,28 @@
 package com.example.springhw31.controller;
 
 import com.example.springhw31.dto.UserDto;
+import com.example.springhw31.service.UserService;
+import lombok.RequiredArgsConstructor;
 import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
 
-/**
- * 회원가입 메서드처럼 UserDto를 파라미터로 받아주세요
- */
-
+@RestController
+@RequiredArgsConstructor
 public class UserController {
 
+  private final UserService userService;
 
+  // 회원 가입
+  @PostMapping("/join")
   public UserDto join(@ModelAttribute UserDto userDto) {
+    return userService.join(userDto);
+  }
 
+  // 로그인
+  @PostMapping("/login")
+  public String login(@ModelAttribute UserDto userDto) {
+    return userService.login(userDto);
   }
 }
diff --git a/src/main/java/com/example/springhw31/entity/User.java b/src/main/java/com/example/springhw31/entity/User.java
index 4e957cc..d2d51f9 100644
--- a/src/main/java/com/example/springhw31/entity/User.java
+++ b/src/main/java/com/example/springhw31/entity/User.java
@@ -1,14 +1,25 @@
 package com.example.springhw31.entity;
 
 
-/**
- * TODO: 완성된 코드 아닙니다~
- */
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
 public class User {
 
+  @Id
+  @GeneratedValue(strategy = GenerationType.AUTO)
+  private Long id;
+
+  @Column(nullable = false, unique = true)
   private String username;
 
+  @Column(nullable = false)
   private String password;
 
+  @Column(nullable = false, unique = true)
   private String nickname;
 }
diff --git a/src/main/java/com/example/springhw31/repository/UserRepository.java b/src/main/java/com/example/springhw31/repository/UserRepository.java
index 53778ec..1722633 100644
--- a/src/main/java/com/example/springhw31/repository/UserRepository.java
+++ b/src/main/java/com/example/springhw31/repository/UserRepository.java
@@ -1,5 +1,10 @@
 package com.example.springhw31.repository;
 
-public class UserRepository {
+import com.example.springhw31.entity.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface UserRepository extends JpaRepository<User, Long> {
+
+    User findByUsername(String username);
 
 }
diff --git a/src/main/java/com/example/springhw31/service/UserService.java b/src/main/java/com/example/springhw31/service/UserService.java
index c3e8928..5ba0a5f 100644
--- a/src/main/java/com/example/springhw31/service/UserService.java
+++ b/src/main/java/com/example/springhw31/service/UserService.java
@@ -1,14 +1,37 @@
 package com.example.springhw31.service;
 
 import com.example.springhw31.dto.UserDto;
+import com.example.springhw31.entity.User;
+import com.example.springhw31.repository.UserRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
 
-/**
- * Controller에 반환할 때도 DTO 객체를 반환합니다.
- */
+@Service
+@RequiredArgsConstructor
 public class UserService {
 
+  private final UserRepository userRepository;
+
+  // 회원 가입
   public UserDto join(UserDto userDto) {
+    User user = new User();
+
+    user.setUsername(userDto.getUsername());
+    user.setPassword(userDto.getPassword());
+    user.setNickname(userDto.getNickname());
+    userRepository.save(user);
 
+    return userDto;
   }
 
+  // 로그인
+  public String login(UserDto userDto) {
+    User user = userRepository.findByUsername(userDto.getUsername());
+    if (user != null) {
+      if (user.getPassword().equals(userDto.getPassword())) {
+        return user.getNickname() + "님, 환영합니다!!";
+      }
+    }
+    return "아이디 및 비밀번호가 일치하지 않습니다.";
+  }
 }
diff --git a/src/main/resources/application.yml b/src/main/resources/application.yml
index 9b78d0c..4676750 100644
--- a/src/main/resources/application.yml
+++ b/src/main/resources/application.yml
@@ -1,8 +1,8 @@
 spring:
   datasource:
-    url: jdbc:mysql://localhost:3306/your_database_name?useSSL=false&serverTimezone=UTC&characterEncoding=UTF-8
-    username: your_username
-    password: your_password
+    url: jdbc:mysql://localhost:3306/spring_study?useSSL=false&serverTimezone=UTC&characterEncoding=UTF-8
+    username: root
+    password: kimna04!
     driver-class-name: com.mysql.cj.jdbc.Driver
 
   jpa: