diff --git a/src/main/java/com/hanaro/hanafun/lesson/controller/LessonController.java b/src/main/java/com/hanaro/hanafun/lesson/controller/LessonController.java
index a707dcb..91b1a80 100644
--- a/src/main/java/com/hanaro/hanafun/lesson/controller/LessonController.java
+++ b/src/main/java/com/hanaro/hanafun/lesson/controller/LessonController.java
@@ -60,8 +60,8 @@ public ResponseEntity<String> uploadImage(@RequestParam("file") MultipartFile fi
 
     // 클래스 등록하기
     @PostMapping("/lesson/create")
-    public void createLesson(@RequestBody CreateLessonReqDto createLessonReqDto) {
-        lessonService.createLesson(createLessonReqDto);
+    public void createLesson(@AuthenticationPrincipal Long userId, @RequestBody CreateLessonReqDto createLessonReqDto) {
+        lessonService.createLesson(userId, createLessonReqDto);
     }
 
     // 클래스 전체 조회 (클래스 탐색)
diff --git a/src/main/java/com/hanaro/hanafun/lesson/dto/request/CreateLessonReqDto.java b/src/main/java/com/hanaro/hanafun/lesson/dto/request/CreateLessonReqDto.java
index 207c653..12ab0c1 100644
--- a/src/main/java/com/hanaro/hanafun/lesson/dto/request/CreateLessonReqDto.java
+++ b/src/main/java/com/hanaro/hanafun/lesson/dto/request/CreateLessonReqDto.java
@@ -6,7 +6,6 @@
 
 @Getter
 public class CreateLessonReqDto {
-    private Long userId;
     private Long categoryId;
     private String title;
     private String location;
diff --git a/src/main/java/com/hanaro/hanafun/lesson/service/LessonService.java b/src/main/java/com/hanaro/hanafun/lesson/service/LessonService.java
index 38d58ba..7f7efae 100644
--- a/src/main/java/com/hanaro/hanafun/lesson/service/LessonService.java
+++ b/src/main/java/com/hanaro/hanafun/lesson/service/LessonService.java
@@ -16,7 +16,7 @@ public interface LessonService {
     LessonInfoResDto lessonInfo(Long lessonId);
 
     // 클래스 등록하기
-    void createLesson(CreateLessonReqDto createLessonReqDto);
+    void createLesson(Long userId, CreateLessonReqDto createLessonReqDto);
 
     // 클래스 전체 조회 (클래스 탐색)
     List<FullLessonResDto> fullLesson();
diff --git a/src/main/java/com/hanaro/hanafun/lesson/service/impl/LessonServiceImpl.java b/src/main/java/com/hanaro/hanafun/lesson/service/impl/LessonServiceImpl.java
index 300e735..7d8e331 100644
--- a/src/main/java/com/hanaro/hanafun/lesson/service/impl/LessonServiceImpl.java
+++ b/src/main/java/com/hanaro/hanafun/lesson/service/impl/LessonServiceImpl.java
@@ -79,8 +79,8 @@ public LessonInfoResDto lessonInfo(Long lessonId) {
     // 클래스 등록하기
     @Transactional
     @Override
-    public void createLesson(CreateLessonReqDto createLessonReqDto) {
-        HostEntity host = hostRepository.findHostEntityByUserEntity_UserId(createLessonReqDto.getUserId());
+    public void createLesson(Long userId, CreateLessonReqDto createLessonReqDto) {
+        HostEntity host = hostRepository.findHostEntityByUserEntity_UserId(userId);
         CategoryEntity category = categoryRepository.findById(createLessonReqDto.getCategoryId()).orElseThrow(() -> new CategoryNotFoundException());
 
         // Lesson 추가
diff --git a/src/main/java/com/hanaro/hanafun/lessondate/controller/LessonDateController.java b/src/main/java/com/hanaro/hanafun/lessondate/controller/LessonDateController.java
index 2cfdfc1..62f1af2 100644
--- a/src/main/java/com/hanaro/hanafun/lessondate/controller/LessonDateController.java
+++ b/src/main/java/com/hanaro/hanafun/lessondate/controller/LessonDateController.java
@@ -7,7 +7,7 @@
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
-import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
 import java.util.List;
@@ -19,7 +19,11 @@ public class LessonDateController {
 
     // 클래스 예약 가능 날짜 출력
     @GetMapping("/lesson/date-select")
-    public ResponseEntity<ApiResponse> availableDate(@RequestBody AvailableDateReqDto availableDateReqDto) {
+    public ResponseEntity<ApiResponse> availableDate(@RequestParam Long lessonId) {
+        AvailableDateReqDto availableDateReqDto = AvailableDateReqDto.builder()
+                .lessonId(lessonId)
+                .build();
+
         List<AvailableDateResDto> availableDateResDtoList = lessonDateService.availableDate(availableDateReqDto);
         return ResponseEntity.ok(new ApiResponse<>(true, "ok", availableDateResDtoList));
     }
diff --git a/src/main/java/com/hanaro/hanafun/lessondate/dto/request/AvailableDateReqDto.java b/src/main/java/com/hanaro/hanafun/lessondate/dto/request/AvailableDateReqDto.java
index be291bd..865db2d 100644
--- a/src/main/java/com/hanaro/hanafun/lessondate/dto/request/AvailableDateReqDto.java
+++ b/src/main/java/com/hanaro/hanafun/lessondate/dto/request/AvailableDateReqDto.java
@@ -1,7 +1,9 @@
 package com.hanaro.hanafun.lessondate.dto.request;
 
+import lombok.Builder;
 import lombok.Getter;
 
+@Builder
 @Getter
 public class AvailableDateReqDto {
     private Long lessonId;
diff --git a/src/main/java/com/hanaro/hanafun/reservation/controller/ReservationController.java b/src/main/java/com/hanaro/hanafun/reservation/controller/ReservationController.java
index 1d4040f..475314f 100644
--- a/src/main/java/com/hanaro/hanafun/reservation/controller/ReservationController.java
+++ b/src/main/java/com/hanaro/hanafun/reservation/controller/ReservationController.java
@@ -54,8 +54,8 @@ public ResponseEntity<ApiResponse> lessonDateDetail(@RequestBody LessonDateDetai
 
     // 클래스 예약하기 (결제 제외)
     @PostMapping("/check")
-    public ResponseEntity<ApiResponse> bookLesson(@RequestBody BookLessonReqDto bookLessonReqDto) {
-        BookLessonResDto bookLessonResDto = reservationService.bookLesson(bookLessonReqDto);
+    public ResponseEntity<ApiResponse> bookLesson(@AuthenticationPrincipal Long userId, @RequestBody BookLessonReqDto bookLessonReqDto) {
+        BookLessonResDto bookLessonResDto = reservationService.bookLesson(userId, bookLessonReqDto);
         return ResponseEntity.ok(new ApiResponse<>(true, "ok", bookLessonResDto));
     }
 
diff --git a/src/main/java/com/hanaro/hanafun/reservation/dto/request/BookLessonReqDto.java b/src/main/java/com/hanaro/hanafun/reservation/dto/request/BookLessonReqDto.java
index 271d8a9..7688d89 100644
--- a/src/main/java/com/hanaro/hanafun/reservation/dto/request/BookLessonReqDto.java
+++ b/src/main/java/com/hanaro/hanafun/reservation/dto/request/BookLessonReqDto.java
@@ -5,7 +5,6 @@
 @Getter
 public class BookLessonReqDto {
     private Long lessondateId;
-    private Long userId;
     private int applicant;  // 예약 수량
     private Long accountId;
     private String password;  // 계좌 비밀번호 확인
diff --git a/src/main/java/com/hanaro/hanafun/reservation/service/ReservationService.java b/src/main/java/com/hanaro/hanafun/reservation/service/ReservationService.java
index 43c42d8..f8a8b93 100644
--- a/src/main/java/com/hanaro/hanafun/reservation/service/ReservationService.java
+++ b/src/main/java/com/hanaro/hanafun/reservation/service/ReservationService.java
@@ -19,7 +19,7 @@ public interface ReservationService {
     LessonDateDetailResDto lessonDateDetail(LessonDateDetailReqDto lessonDateDetailReqDto);
 
     // 클래스 예약하기 (결제 제외)
-    BookLessonResDto bookLesson(BookLessonReqDto bookLessonReqDto);
+    BookLessonResDto bookLesson(Long userId, BookLessonReqDto bookLessonReqDto);
 
     // 클래스 취소하기 (환불 제외)
     void cancelLesson(CancelLessonReqDto cancelLessonReqDto);
diff --git a/src/main/java/com/hanaro/hanafun/reservation/service/impl/ReservationServiceImpl.java b/src/main/java/com/hanaro/hanafun/reservation/service/impl/ReservationServiceImpl.java
index 3eba127..bdd040c 100644
--- a/src/main/java/com/hanaro/hanafun/reservation/service/impl/ReservationServiceImpl.java
+++ b/src/main/java/com/hanaro/hanafun/reservation/service/impl/ReservationServiceImpl.java
@@ -165,7 +165,7 @@ public LessonDateDetailResDto lessonDateDetail(LessonDateDetailReqDto lessonDate
     // 클래스 예약하기 (결제 제외)
     @Transactional
     @Override
-    public BookLessonResDto bookLesson(BookLessonReqDto bookLessonReqDto) {
+    public BookLessonResDto bookLesson(Long userId, BookLessonReqDto bookLessonReqDto) {
         // 계좌 비밀번호 확인
         AccountEntity account = accountRepository.findById(bookLessonReqDto.getAccountId()).orElseThrow(() -> new AccountNotFoundException());
         if (!account.getPassword().equals(bookLessonReqDto.getPassword())) {
@@ -184,8 +184,7 @@ public BookLessonResDto bookLesson(BookLessonReqDto bookLessonReqDto) {
         }
 
         // 해당 날짜에 예약 이미 있는지 확인
-        Optional<ReservationEntity> existingReservation = reservationRepository.findReservationEntityByUserEntity_UserIdAndLessonDateEntity_LessondateId(
-                bookLessonReqDto.getUserId(), bookLessonReqDto.getLessondateId());
+        Optional<ReservationEntity> existingReservation = reservationRepository.findReservationEntityByUserEntity_UserIdAndLessonDateEntity_LessondateId(userId, bookLessonReqDto.getLessondateId());
         if (existingReservation.isPresent()) {
             return BookLessonResDto.builder()
                     .message("이미 예약이 존재합니다.")
@@ -193,7 +192,7 @@ public BookLessonResDto bookLesson(BookLessonReqDto bookLessonReqDto) {
         }
 
         // 예약 추가
-        UserEntity user = userRepository.findUserEntityByUserId(bookLessonReqDto.getUserId()).orElseThrow(() -> new UserNotFoundException());
+        UserEntity user = userRepository.findUserEntityByUserId(userId).orElseThrow(() -> new UserNotFoundException());
         ReservationEntity reservation = ReservationEntity.builder()
                 .userEntity(user)
                 .lessonDateEntity(lessonDate)