diff --git a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/controller/ChatMessageController.kt b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/controller/ChatMessageController.kt
index 37fad20..53aa0fe 100644
--- a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/controller/ChatMessageController.kt
+++ b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/controller/ChatMessageController.kt
@@ -15,7 +15,7 @@ import org.springframework.web.bind.annotation.RestController
 @RestController
 @RequestMapping("/api/userchat/rooms")
 class ChatMessageController(
-    private val msgSvc: ChatMessageService,
+    private val messageService: ChatMessageService,
     private val messagingTemplate: SimpMessagingTemplate,
 ) {
     @GetMapping("/{roomId}/messages")
@@ -26,9 +26,9 @@ class ChatMessageController(
     ): ResponseEntity<ApiResponse<Any>> {
         val messages =
             if (after == null) {
-                msgSvc.getlistbefore(roomId, limit)
+                messageService.getlistbefore(roomId, limit)
             } else {
-                msgSvc.getlistafter(roomId, after)
+                messageService.getlistafter(roomId, after)
             }
         return ResponseEntity.ok(ApiResponse(msg = "메시지 조회", data = messages))
     }
@@ -38,7 +38,7 @@ class ChatMessageController(
         @PathVariable roomId: Long,
         @RequestBody req: ChatMessageService.SendMessageReq,
     ): ResponseEntity<ApiResponse<Any>> {
-        val saved = msgSvc.send(roomId, req)
+        val saved = messageService.send(roomId, req)
         messagingTemplate.convertAndSend(
             "/topic/userchat/$roomId",
             ApiResponse(msg = "메시지 전송", data = saved),
diff --git a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/service/ChatMessageService.kt b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/service/ChatMessageService.kt
index 26f73a0..51574b8 100644
--- a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/service/ChatMessageService.kt
+++ b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatmessage/service/ChatMessageService.kt
@@ -8,32 +8,29 @@ import org.springframework.transaction.annotation.Transactional
 
 @Service
 class ChatMessageService(
-    private val msgRepository: ChatMessageRepository,
+    private val messageRepository: ChatMessageRepository,
     private val roomRepository: ChatRoomRepository,
 ) {
     data class SendMessageReq(val senderId: Long, val content: String)
 
+    @Transactional(readOnly = true)
     fun getlistbefore(
         roomId: Long,
         limit: Int,
-    ): List<ChatMessage> = msgRepository.findTop50ByRoomIdOrderByIdDesc(roomId).asReversed()
+    ): List<ChatMessage> = messageRepository.findTop50ByRoomIdOrderByIdDesc(roomId).asReversed()
 
+    @Transactional(readOnly = true)
     fun getlistafter(
         roomId: Long,
         afterId: Long,
-    ): List<ChatMessage> = msgRepository.findByRoomIdAndIdGreaterThanOrderByIdAsc(roomId, afterId)
-
-    @Transactional
-    fun deleteByRoom(roomId: Long) {
-        msgRepository.deleteByRoomId(roomId)
-    }
+    ): List<ChatMessage> = messageRepository.findByRoomIdAndIdGreaterThanOrderByIdAsc(roomId, afterId)
 
     @Transactional
     fun send(
         roomId: Long,
         req: SendMessageReq,
     ): ChatMessage {
-        val saved = msgRepository.save(ChatMessage(roomId = roomId, senderId = req.senderId, content = req.content))
+        val saved = messageRepository.save(ChatMessage(roomId = roomId, senderId = req.senderId, content = req.content))
         roomRepository.findById(roomId).ifPresent {
             roomRepository.save(it.copy(updatedAt = saved.createdAt, lastMessageId = saved.id))
         }
diff --git a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/controller/ChatRoomController.kt b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/controller/ChatRoomController.kt
index 536a68b..5dda47b 100644
--- a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/controller/ChatRoomController.kt
+++ b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/controller/ChatRoomController.kt
@@ -14,7 +14,7 @@ import org.springframework.web.bind.annotation.RestController
 @RestController
 @RequestMapping("/api/userchat/rooms")
 class ChatRoomController(
-    private val roomSvc: ChatRoomService,
+    private val roomService: ChatRoomService,
 ) {
     data class StartChatReq(val guideId: Long, val userId: Long)
 
@@ -25,7 +25,7 @@ class ChatRoomController(
     fun startChat(
         @RequestBody req: StartChatReq,
     ): ResponseEntity<ApiResponse<Map<String, Long>>> {
-        val roomId = roomSvc.exceptOneToOneRoom(req.guideId, req.userId).id!!
+        val roomId = roomService.exceptOneToOneRoom(req.guideId, req.userId).id!!
         return ResponseEntity.ok(ApiResponse(msg = "채팅방 시작", data = mapOf("roomId" to roomId)))
     }
 
@@ -34,12 +34,12 @@ class ChatRoomController(
         @PathVariable roomId: Long,
         @RequestBody req: DeleteChatReq,
     ): ResponseEntity<ApiResponse<Unit>> {
-        roomSvc.deleteByOwner(roomId, req.userId)
+        roomService.deleteByOwner(roomId, req.userId)
         return ResponseEntity.ok(ApiResponse("채팅방 삭제 완료"))
     }
 
     @GetMapping("/{roomId}")
     fun get(
         @PathVariable roomId: Long,
-    ) = ResponseEntity.ok(ApiResponse(msg = "채팅방 조회", data = roomSvc.get(roomId)))
+    ) = ResponseEntity.ok(ApiResponse(msg = "채팅방 조회", data = roomService.get(roomId)))
 }
diff --git a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/service/ChatRoomService.kt b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/service/ChatRoomService.kt
index 35e446d..553e927 100644
--- a/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/service/ChatRoomService.kt
+++ b/src/main/kotlin/com/back/koreaTravelGuide/domain/userChat/chatroom/service/ChatRoomService.kt
@@ -27,6 +27,7 @@ class ChatRoomService(
         )
     }
 
+    @Transactional(readOnly = true)
     fun get(roomId: Long): ChatRoom =
         roomRepository.findById(roomId)
             .orElseThrow { NoSuchElementException("room not found: $roomId") }