diff --git a/api/src/main/kotlin/com/backgu/amaker/api/chat/service/ChatRoomFacadeService.kt b/api/src/main/kotlin/com/backgu/amaker/api/chat/service/ChatRoomFacadeService.kt
index 7b87e516..aa2df298 100644
--- a/api/src/main/kotlin/com/backgu/amaker/api/chat/service/ChatRoomFacadeService.kt
+++ b/api/src/main/kotlin/com/backgu/amaker/api/chat/service/ChatRoomFacadeService.kt
@@ -37,7 +37,7 @@ class ChatRoomFacadeService(
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getById(workspaceId)
 
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         // 유저의 채팅방 목록 조회
         val chatRoomMys: List<ChatRoomUser> = chatRoomUserService.findAllByUser(user)
@@ -86,7 +86,7 @@ class ChatRoomFacadeService(
     ): BriefChatRoomViewDto {
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getById(workspaceId)
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         val chatRooms: List<ChatRoom> = chatRoomService.findChatRoomsByWorkspaceId(workspaceId)
         val chatRoomUserMap: Map<Long, List<ChatRoomUser>> =
@@ -111,7 +111,7 @@ class ChatRoomFacadeService(
     ): BriefChatRoomViewDto {
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getById(workspaceId)
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         val chatRooms: List<ChatRoom> = chatRoomService.findNotRegisteredChatRoomsByWorkspaceId(workspaceId, userId)
         val chatRoomUserMap: Map<Long, List<ChatRoomUser>> =
@@ -154,7 +154,7 @@ class ChatRoomFacadeService(
     ): ChatRoomUser {
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getById(workspaceId)
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         val chatRoom = chatRoomService.getChatRoomByWorkspaceIdAndChatRoomId(workspaceId, chatRoomId)
         chatRoomUserService.validateUserNotInChatRoom(user, chatRoom)
diff --git a/api/src/main/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceFacadeService.kt b/api/src/main/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceFacadeService.kt
index a7ab81a0..28c25136 100644
--- a/api/src/main/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceFacadeService.kt
+++ b/api/src/main/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceFacadeService.kt
@@ -62,11 +62,9 @@ class WorkspaceFacadeService(
         userId: String,
         workspaceId: Long,
     ): WorkspaceDto {
-        val user: User = userService.getById(userId)
+        workspaceUserService.validateUserInWorkspace(userId, workspaceId)
         val workspace: Workspace = workspaceService.getWorkspaceById(workspaceId)
 
-        workspaceUserService.validUserInWorkspace(user, workspace)
-
         return WorkspaceDto.of(workspace)
     }
 
@@ -94,7 +92,7 @@ class WorkspaceFacadeService(
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getWorkspaceById(workspaceId)
 
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         val workspaceUsers = workspaceUserService.findWorkSpaceUserByWorkspaceId(workspaceId)
 
@@ -120,7 +118,7 @@ class WorkspaceFacadeService(
         val user: User = userService.getById(userId)
         val workspace: Workspace = workspaceService.getWorkspaceById(workspaceId)
 
-        workspaceUserService.validUserInWorkspace(user, workspace)
+        workspaceUserService.validateUserWorkspaceInActive(user, workspace)
 
         return ChatRoomDto
             .of(chatRoomService.getDefaultChatRoomByWorkspace(workspace))
diff --git a/api/src/test/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceUserServiceTest.kt b/api/src/test/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceUserServiceTest.kt
index 99fa2dce..c3bc4f0e 100644
--- a/api/src/test/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceUserServiceTest.kt
+++ b/api/src/test/kotlin/com/backgu/amaker/api/workspace/service/WorkspaceUserServiceTest.kt
@@ -33,7 +33,7 @@ class WorkspaceUserServiceTest : IntegrationTest() {
 
         // when & then
         assertThatCode {
-            workspaceUserService.validUserInWorkspace(user, workspace)
+            workspaceUserService.validateUserWorkspaceInActive(user, workspace)
         }.doesNotThrowAnyException()
     }
 
@@ -50,7 +50,7 @@ class WorkspaceUserServiceTest : IntegrationTest() {
         fixtures.workspaceUser.createPersistedWorkspaceUser(workspaceId = workspace.id, leaderId = diffUser)
 
         // when & then
-        assertThatThrownBy { workspaceUserService.validUserInWorkspace(user, workspace) }
+        assertThatThrownBy { workspaceUserService.validateUserWorkspaceInActive(user, workspace) }
             .isInstanceOf(BusinessException::class.java)
             .hasMessage("워크스페이스에 접근할 수 없습니다.")
             .extracting("statusCode")
diff --git a/infra/src/main/kotlin/com/backgu/amaker/application/workspace/WorkspaceUserService.kt b/infra/src/main/kotlin/com/backgu/amaker/application/workspace/WorkspaceUserService.kt
index d016d263..075c7faf 100644
--- a/infra/src/main/kotlin/com/backgu/amaker/application/workspace/WorkspaceUserService.kt
+++ b/infra/src/main/kotlin/com/backgu/amaker/application/workspace/WorkspaceUserService.kt
@@ -33,7 +33,16 @@ class WorkspaceUserService(
     fun findWorkSpaceUserByWorkspaceId(workspaceId: Long): List<WorkspaceUser> =
         workspaceUserRepository.findByWorkspaceId(workspaceId).map { it.toDomain() }
 
-    fun validUserInWorkspace(
+    fun validateUserInWorkspace(
+        userId: String,
+        workspaceId: Long,
+    ) {
+        if (!workspaceUserRepository.existsByUserIdAndWorkspaceId(userId, workspaceId)) {
+            throw BusinessException(StatusCode.WORKSPACE_UNREACHABLE)
+        }
+    }
+
+    fun validateUserWorkspaceInActive(
         userId: String,
         workspaceId: Long,
     ) {
@@ -47,11 +56,11 @@ class WorkspaceUserService(
         }
     }
 
-    fun validUserInWorkspace(
+    fun validateUserWorkspaceInActive(
         user: User,
         workspace: Workspace,
     ) {
-        validUserInWorkspace(user.id, workspace.id)
+        validateUserWorkspaceInActive(user.id, workspace.id)
     }
 
     fun validateUserNotRelatedInWorkspace(
diff --git a/realtime/src/main/kotlin/com/backgu/amaker/realtime/session/service/SessionFacadeService.kt b/realtime/src/main/kotlin/com/backgu/amaker/realtime/session/service/SessionFacadeService.kt
index 758cec85..20c62e64 100644
--- a/realtime/src/main/kotlin/com/backgu/amaker/realtime/session/service/SessionFacadeService.kt
+++ b/realtime/src/main/kotlin/com/backgu/amaker/realtime/session/service/SessionFacadeService.kt
@@ -22,7 +22,7 @@ class SessionFacadeService(
         workspaceId: Long,
         workspaceRealTimeSession: RealTimeSession<WebSocketSession>,
     ) {
-        workspaceUserService.validUserInWorkspace(userId, workspaceId)
+        workspaceUserService.validateUserWorkspaceInActive(userId, workspaceId)
 
         workspaceSessionService.findDropOutSessionIfLimit(workspaceId, userId).forEach {
             if (it.realtimeId != serverConfig.id) {