diff --git a/apps/client/src/scenes/game/application/network/handlers/PlayerSyncHandler.ts b/apps/client/src/scenes/game/application/network/handlers/PlayerSyncHandler.ts
index fc7c7e6..fe4a42c 100644
--- a/apps/client/src/scenes/game/application/network/handlers/PlayerSyncHandler.ts
+++ b/apps/client/src/scenes/game/application/network/handlers/PlayerSyncHandler.ts
@@ -29,11 +29,13 @@
 export class PlayerSyncHandler {
   private readonly worldContainer: Container;
   private readonly playerRepository: PlayerRepository;
+  private readonly myId: string;
   private readonly playerControllerFactory: PlayerControllerFactory;
 
   constructor({ worldContainer, playerRepository, myId, appearanceResolver }: PlayerSyncHandlerOptions) {
     this.worldContainer = worldContainer;
     this.playerRepository = playerRepository;
+    this.myId = myId;
     this.playerControllerFactory = new PlayerControllerFactory({
       myId,
       appearanceResolver,
@@ -52,9 +54,13 @@
     this.replacePlayerController(payload.id, payload);
   };
 
-  /** プレイヤー差分更新を反映する */
+  /** プレイヤー差分更新を反映する（自分自身は除外する） */
   public handlePlayerUpdates = (changedPlayers: UpdatePlayersPayload): void => {
     changedPlayers.forEach((playerData) => {
+      if (playerData.id === this.myId) {
+        return;
+      }
+
       const target = this.playerRepository.getById(playerData.id);
       if (target && target instanceof RemotePlayerController) {
         target.applyRemoteUpdate({ x: playerData.x, y: playerData.y });
diff --git a/apps/server/src/application/coordinators/startGameCoordinator.ts b/apps/server/src/application/coordinators/startGameCoordinator.ts
index 72407a7..1d09b4a 100644
--- a/apps/server/src/application/coordinators/startGameCoordinator.ts
+++ b/apps/server/src/application/coordinators/startGameCoordinator.ts
@@ -102,7 +102,6 @@
     roomId: updatedRoom.roomId,
     playerIds: sessionPlayerIds,
     playerNamesById,
-    recipientPlayerIds: humanPlayerIds,
     gameSession: gameManager,
     bombStore: gameManager,
     onGameEnd: () => {
diff --git a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
index c071fea..ebfd42f 100644
--- a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
+++ b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
@@ -48,8 +48,8 @@
 /** ゲーム系ユースケースが利用する送信出力ポート */
 export interface GameOutputPort {
   publishPongToSocket(payload: PongPayload): void;
-  publishUpdatePlayersToSocket(
-    socketId: string,
+  publishUpdatePlayersToRoom(
+    roomId: domain.room.Room["roomId"],
     players: UpdatePlayersPayload,
   ): void;
   publishMapCellUpdatesToRoom(
@@ -98,7 +98,7 @@
 /** start-game 系フローで利用する送信出力ポート */
 export type StartGameOutputPort = Pick<
   GameOutputPort,
-  | "publishUpdatePlayersToSocket"
+  | "publishUpdatePlayersToRoom"
   | "publishMapCellUpdatesToRoom"
   | "publishGameEndToRoom"
   | "publishGameResultToRoom"
diff --git a/apps/server/src/domains/game/application/useCases/startGameUseCase.ts b/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
index c800c3c..17c2776 100644
--- a/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
@@ -15,22 +15,10 @@
 } from "@server/logging/index";
 import { createBotBombActionHandler } from "../services/bot/index.js";
 
-const excludeRecipientFromPlayerUpdates = <
-  TPlayerUpdate extends { id: string },
->(
-  playerUpdates: TPlayerUpdate[],
-  recipientId: string,
-): TPlayerUpdate[] => {
-  return playerUpdates.filter(
-    (playerUpdate) => playerUpdate.id !== recipientId,
-  );
-};
-
 type StartGameUseCaseParams = {
   roomId: string;
   playerIds: string[];
   playerNamesById: Record<string, string>;
-  recipientPlayerIds?: string[];
   gameSession: StartGamePort;
   bombStore: BombPlacementPort;
   onGameEnd: () => void;
@@ -42,13 +30,11 @@
   roomId,
   playerIds,
   playerNamesById,
-  recipientPlayerIds,
   gameSession,
   bombStore,
   onGameEnd,
   output,
 }: StartGameUseCaseParams) => {
-  const updateRecipients = recipientPlayerIds ?? playerIds;
   const handleBotBombAction = createBotBombActionHandler({
     roomId,
     bombStore,
@@ -68,18 +54,7 @@
     {
       onTick: (tickData) => {
         if (tickData.playerUpdates.length > 0) {
-          updateRecipients.forEach((playerId) => {
-            const updatesForPlayer = excludeRecipientFromPlayerUpdates(
-              tickData.playerUpdates,
-              playerId,
-            );
-
-            if (updatesForPlayer.length === 0) {
-              return;
-            }
-
-            output.publishUpdatePlayersToSocket(playerId, updatesForPlayer);
-          });
+          output.publishUpdatePlayersToRoom(roomId, tickData.playerUpdates);
         }
 
         if (tickData.cellUpdates.length > 0) {
diff --git a/apps/server/src/network/handlers/game/createGameOutputAdapter.ts b/apps/server/src/network/handlers/game/createGameOutputAdapter.ts
index c8f85b3..4832f45 100644
--- a/apps/server/src/network/handlers/game/createGameOutputAdapter.ts
+++ b/apps/server/src/network/handlers/game/createGameOutputAdapter.ts
@@ -50,13 +50,13 @@
     publishPongToSocket: (payload: PongPayload) => {
       common.emitToSocket(protocol.SocketEvents.PONG, payload);
     },
-    publishUpdatePlayersToSocket: (
-      socketId: string,
+    publishUpdatePlayersToRoom: (
+      roomId: RoomId,
       players: UpdatePlayersPayload,
     ) => {
       const sanitizedPlayers = sanitizeUpdatePlayersPayload(players);
-      common.emitToSocketById(
-        socketId,
+      common.emitToRoom(
+        roomId,
         protocol.SocketEvents.UPDATE_PLAYERS,
         sanitizedPlayers,
       );