diff --git a/apps/server/src/domains/room/application/useCases/joinRoomUseCase.ts b/apps/server/src/domains/room/application/useCases/joinRoomUseCase.ts
index 8ab6699..4f9a1fd 100644
--- a/apps/server/src/domains/room/application/useCases/joinRoomUseCase.ts
+++ b/apps/server/src/domains/room/application/useCases/joinRoomUseCase.ts
@@ -14,10 +14,10 @@
   roomManager: JoinRoomPort;
   socketId: string;
   data: roomTypes.JoinRoomPayload;
-  output: RoomOutputPort;
+  output: Pick<RoomOutputPort, "publishJoinRejectedToSocket">;
 };
 
-/** 参加イベントを受け取り，ルーム更新を配信する */
+/** 参加イベントを受け取り，参加可否を判定する */
 export const joinRoomUseCase = ({
   roomManager,
   socketId,
@@ -50,7 +50,5 @@
     return joinResult;
   }
 
-  output.publishRoomUpdateToRoom(roomId, joinResult.room);
-
   return joinResult;
 };
diff --git a/apps/server/src/network/handlers/room/registerRoomHandlers.ts b/apps/server/src/network/handlers/room/registerRoomHandlers.ts
index d5729b1..d888b40 100644
--- a/apps/server/src/network/handlers/room/registerRoomHandlers.ts
+++ b/apps/server/src/network/handlers/room/registerRoomHandlers.ts
@@ -21,7 +21,7 @@
   const roomOutputAdapter = createRoomOutputAdapter(common);
 
   // 参加要求のペイロード検証と参加処理を実行する
-  socket.on(protocol.SocketEvents.JOIN_ROOM, (data: unknown) => {
+  socket.on(protocol.SocketEvents.JOIN_ROOM, async (data: unknown) => {
     if (!isJoinRoomPayload(data)) {
       logEvent("Network", {
         event: "JOIN_ROOM",
@@ -61,7 +61,7 @@
         return;
 
       case "joined":
-        socket.join(roomId);
+        await socket.join(roomId);
         roomOutputAdapter.publishRoomUpdateToRoom(roomId, joinResult.room);
         logEvent("RoomUseCase", {
           event: "ROOM_UPDATE",