diff --git a/src/main/java/com/keepgoing/keepserver/domain/user/controller/UserController.java b/src/main/java/com/keepgoing/keepserver/domain/user/controller/UserController.java
index a9a33616..e8358fee 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/user/controller/UserController.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/user/controller/UserController.java
@@ -25,39 +25,27 @@ public class UserController {
 
     private final UserService userService;
 
-    private final UserServiceImpl userServiceImpl;
-
     @Operation(summary = "로그인", description = "로그인을 진행합니다.")
     @PostMapping("/signin")
     public ResponseEntity<?> authenticateUser(@RequestBody LoginRequest loginRequest) {
-        return ResponseEntity.ok().body(userServiceImpl.authenticateAndGenerateJWT(loginRequest.getEmail(), loginRequest.getPassword()));
+        return ResponseEntity.ok().body(userService.authenticateAndGenerateJWT(loginRequest.getEmail(), loginRequest.getPassword()));
     }
 
     @Operation(summary = "회원가입", description = "회원가입을 진행합니다.")
     @PostMapping("/signup")
     public ResponseEntity<?> registerAndAuthenticateUser(@RequestBody SignupRequest signupRequest) throws BusinessException {
-
-        /* 유저 등록 */
-        userService.registerUser(signupRequest);
-
-        JwtResponse jwtResponse = userServiceImpl.authenticateAndGenerateJWT(signupRequest.getEmail(), signupRequest.getPassword());
-        ApiResponse<JwtResponse> response = ApiResponse.setApiResponse(true, "회원 가입이 완료 되었습니다!", jwtResponse);
-
-        return ResponseEntity.ok().body(response);
+        return ResponseEntity.ok().body(userService.registerUser(signupRequest));
     }
 
     @Operation(summary = "프로필", description = "토큰을 이용하여 유저 정보와 대여한 기자재 및 도서 목록을 조회합니다.")
     @GetMapping("/userinfo")
     public UserProfileDto provideUserInfo(Authentication authentication) {
-        String userEmail = authentication.getName();
-        return userService.provideUserInfo(userEmail);
+        return userService.provideUserInfo(authentication);
     }
 
     @Operation(summary = "프로필 수정", description = "유저 정보를 수정합니다.")
     @PutMapping("/userfix")
-    public void updateUserData(@RequestBody UserInfoRequest request, Authentication authentication) {
-        String userName = authentication.getName();
-        userServiceImpl.updateUserData(request, userName);
-        ResponseEntity.ok().body("");
+    public ResponseEntity<String> updateUserData(@RequestBody UserInfoRequest request, Authentication authentication) {
+        return userService.updateUserData(request, authentication);
     }
 }
diff --git a/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserService.java b/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserService.java
index 4f4e2c82..dc5a225a 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserService.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserService.java
@@ -3,10 +3,15 @@
 import com.keepgoing.keepserver.domain.user.payload.request.SignupRequest;
 import com.keepgoing.keepserver.domain.user.payload.request.UserInfoRequest;
 import com.keepgoing.keepserver.domain.user.payload.request.UserProfileDto;
+import com.keepgoing.keepserver.domain.user.payload.response.ApiResponse;
+import com.keepgoing.keepserver.domain.user.payload.response.JwtResponse;
 import com.keepgoing.keepserver.global.exception.BusinessException;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.Authentication;
 
 public interface UserService {
-    void registerUser(SignupRequest signupRequest) throws BusinessException;
-    void updateUserData(UserInfoRequest request, String email);
-    UserProfileDto provideUserInfo(String userEmail);
+    ApiResponse<JwtResponse> registerUser(SignupRequest signupRequest) throws BusinessException;
+    ResponseEntity<String> updateUserData(UserInfoRequest request, Authentication authentication);
+    UserProfileDto provideUserInfo(Authentication authentication);
+    JwtResponse authenticateAndGenerateJWT(String email, String password);
 }
\ No newline at end of file
diff --git a/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserServiceImpl.java b/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserServiceImpl.java
index 993beb84..4c541350 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserServiceImpl.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/user/service/user/UserServiceImpl.java
@@ -12,6 +12,7 @@
 import com.keepgoing.keepserver.domain.user.payload.request.SignupRequest;
 import com.keepgoing.keepserver.domain.user.payload.request.UserInfoRequest;
 import com.keepgoing.keepserver.domain.user.payload.request.UserProfileDto;
+import com.keepgoing.keepserver.domain.user.payload.response.ApiResponse;
 import com.keepgoing.keepserver.domain.user.payload.response.JwtResponse;
 import com.keepgoing.keepserver.domain.user.repository.user.UserRepository;
 import com.keepgoing.keepserver.domain.user.security.jwt.JwtUtils;
@@ -19,14 +20,15 @@
 import com.keepgoing.keepserver.global.exception.BusinessException;
 import com.keepgoing.keepserver.global.exception.device.DeviceException;
 import com.keepgoing.keepserver.global.exception.error.ErrorCode;
-import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
 import java.util.List;
 
@@ -45,35 +47,30 @@ public class UserServiceImpl implements UserService {
 
     @Override
     @Transactional
-    public void registerUser(SignupRequest signupRequest) throws BusinessException {
-        if (userRepository.existsByEmail(signupRequest.getEmail())) {
-            throw new BusinessException(ErrorCode.EMAIL_BAD_REQUEST);
-        }
-        User user = User.registerUser(
-                signupRequest.getEmail(), encoder.encode(signupRequest.getPassword()),
-                signupRequest.getName(), signupRequest.isTeacher()
-        );
+    public ApiResponse<JwtResponse> registerUser(SignupRequest signupRequest) throws BusinessException {
+        validateEmail(signupRequest.getEmail());
+        User user = createUser(signupRequest);
         userRepository.save(user);
+        JwtResponse jwtResponse = authenticateAndGenerateJWT(signupRequest.getEmail(), signupRequest.getPassword());
+        return ApiResponse.setApiResponse(true, "회원 가입이 완료 되었습니다!", jwtResponse);
     }
 
+    @Override
     @Transactional
-    public void updateUserData(UserInfoRequest request, String email) {
-        User user = userRepository.findByEmailEquals(email)
-                .orElseThrow(() -> new BusinessException(ErrorCode.NOT_FOUND));
-
-        user.fixUserData(
-                request.getEmail(),
-                request.getName()
-        );
+    public ResponseEntity<String> updateUserData(UserInfoRequest request, Authentication authentication) {
+        String userEmail = getEmailFromAuthentication(authentication);
+        User user = findUserByEmail(userEmail);
+        updateUser(user, request);
+        return ResponseEntity.ok().body("");
     }
 
     @Override
-    public UserProfileDto provideUserInfo(String userEmail) {
-        User user = userRepository.findByEmailEquals(userEmail).orElseThrow(DeviceException::userNotFound);
+    public UserProfileDto provideUserInfo(Authentication authentication) {
+        String userEmail = getNameByAuthentication(authentication);
+        User user = findUserByEmail(userEmail);
         List<DeviceResponseDto> borrowedDevicesDto = getBorrowedDevicesForUser(user);
         List<BookResponseDto> borrowedBooksDto = getBorrowedBooksForUser(user);
         hideUserPassword(user);
-
         return new UserProfileDto(user, borrowedDevicesDto, borrowedBooksDto);
     }
 
@@ -102,4 +99,36 @@ private List<BookResponseDto> getBorrowedBooksForUser(User user) {
     private void hideUserPassword(User user) {
         user.hidePassword("");
     }
+
+    private String getNameByAuthentication(Authentication authentication) {
+        return authentication.getName();
+    }
+
+    private void validateEmail(String email) throws BusinessException {
+        if (userRepository.existsByEmail(email)) {
+            throw new BusinessException(ErrorCode.EMAIL_BAD_REQUEST);
+        }
+    }
+
+    private User createUser(SignupRequest signupRequest) {
+        return User.registerUser(
+                signupRequest.getEmail(),
+                encoder.encode(signupRequest.getPassword()),
+                signupRequest.getName(),
+                signupRequest.isTeacher()
+        );
+    }
+
+    private String getEmailFromAuthentication(Authentication authentication) {
+        return getNameByAuthentication(authentication);
+    }
+
+    private User findUserByEmail(String email) {
+        return userRepository.findByEmailEquals(email)
+                .orElseThrow(DeviceException::userNotFound);
+    }
+
+    private void updateUser(User user, UserInfoRequest request) {
+        user.fixUserData(request.getEmail(), request.getName());
+    }
 }