diff --git a/apps/client/src/network/handlers/GameHandler.ts b/apps/client/src/network/handlers/GameHandler.ts
index 8005556..979e679 100644
--- a/apps/client/src/network/handlers/GameHandler.ts
+++ b/apps/client/src/network/handlers/GameHandler.ts
@@ -12,6 +12,7 @@
   GameStartPayload,
   MovePayload,
   NewPlayerPayload,
+  PlaceBombPayload,
   RemovePlayerPayload,
   UpdateMapCellsPayload,
   UpdatePlayersPayload,
@@ -40,7 +41,7 @@
   onBombPlaced: (callback: (payload: BombPlacedPayload) => void) => void;
   offBombPlaced: (callback: (payload: BombPlacedPayload) => void) => void;
   sendMove: (x: number, y: number) => void;
-  sendPlaceBomb: (payload: BombPlacedPayload) => void;
+  sendPlaceBomb: (payload: PlaceBombPayload) => void;
   readyForGame: () => void;
 };
 
diff --git a/apps/client/src/scenes/game/GameManager.ts b/apps/client/src/scenes/game/GameManager.ts
index c56cc12..c3c61d7 100644
--- a/apps/client/src/scenes/game/GameManager.ts
+++ b/apps/client/src/scenes/game/GameManager.ts
@@ -4,8 +4,7 @@
  * マップ，ネットワーク同期，ゲームループを統合する
  */
 import { Application, Container, Ticker } from "pixi.js";
-import { createBombIdFromPayload } from "@repo/shared";
-import type { BombNetworkPayload } from "@repo/shared";
+import type { BombPlacedPayload } from "@repo/shared";
 import { socketManager } from "@client/network/SocketManager";
 import { GameMapController } from "./entities/map/GameMapController";
 import { BombManager } from "./entities/bomb/BombManager";
@@ -44,15 +43,11 @@
     if (!placed) return null;
 
     socketManager.game.sendPlaceBomb(placed.payload);
-    return placed.bombId;
+    return placed.tempBombId;
   }
 
-  public upsertBombFromNetwork(bombId: string, payload: BombNetworkPayload): void {
-    this.bombManager?.upsertBombFromNetwork(bombId, payload);
-  }
-
-  public removeBomb(bombId: string): void {
-    this.bombManager?.removeBomb(bombId);
+  public applyPlacedBomb(payload: BombPlacedPayload): void {
+    this.bombManager?.applyPlacedBomb(payload);
   }
   
   // 入力と状態管理
@@ -102,8 +97,7 @@
       onGameStart: this.setGameStart.bind(this),
       onGameEnd: this.lockInput.bind(this),
       onBombPlacedFromNetwork: (payload) => {
-        const bombId = createBombIdFromPayload(payload);
-        this.upsertBombFromNetwork(bombId, payload);
+        this.applyPlacedBomb(payload);
       },
     });
     this.networkSync.bind();
diff --git a/apps/client/src/scenes/game/application/GameNetworkSync.ts b/apps/client/src/scenes/game/application/GameNetworkSync.ts
index 783e3ca..25fc668 100644
--- a/apps/client/src/scenes/game/application/GameNetworkSync.ts
+++ b/apps/client/src/scenes/game/application/GameNetworkSync.ts
@@ -5,7 +5,7 @@
  */
 import { Container } from "pixi.js";
 import type {
-  BombNetworkPayload,
+  BombPlacedPayload,
   CurrentPlayersPayload,
   GameStartPayload,
   NewPlayerPayload,
@@ -27,7 +27,7 @@
   gameMap: GameMapController;
   onGameStart: (startTime: number) => void;
   onGameEnd: () => void;
-  onBombPlacedFromNetwork: (payload: BombNetworkPayload) => void;
+  onBombPlacedFromNetwork: (payload: BombPlacedPayload) => void;
 };
 
 /** ゲーム中のネットワークイベント購読と同期処理を管理する */
@@ -38,7 +38,7 @@
   private gameMap: GameMapController;
   private onGameStart: (startTime: number) => void;
   private onGameEnd: () => void;
-  private onBombPlacedFromNetwork: (payload: BombNetworkPayload) => void;
+  private onBombPlacedFromNetwork: (payload: BombPlacedPayload) => void;
   private isBound = false;
 
   private debugLog = (message: string) => {
@@ -99,7 +99,7 @@
     this.onGameEnd();
   };
 
-  private handleBombPlaced = (payload: BombNetworkPayload) => {
+  private handleBombPlaced = (payload: BombPlacedPayload) => {
     this.onBombPlacedFromNetwork(payload);
   };
 
diff --git a/apps/client/src/scenes/game/entities/bomb/BombManager.ts b/apps/client/src/scenes/game/entities/bomb/BombManager.ts
index dfd69fb..ee73ace 100644
--- a/apps/client/src/scenes/game/entities/bomb/BombManager.ts
+++ b/apps/client/src/scenes/game/entities/bomb/BombManager.ts
@@ -5,8 +5,7 @@
  */
 import type { Container } from "pixi.js";
 import { config } from "@client/config";
-import { createBombIdFromPayload } from "@repo/shared";
-import type { BombNetworkPayload } from "@repo/shared";
+import type { BombPlacedPayload, PlaceBombPayload } from "@repo/shared";
 import { LocalPlayerController } from "@client/scenes/game/entities/player/PlayerController";
 import { BombController } from "./BombController";
 import type { GamePlayers } from "@client/scenes/game/application/game.types";
@@ -15,14 +14,17 @@
 export type ElapsedMsProvider = () => number;
 
 /** 爆弾の描画更新に使う入力データ型 */
-export type BombRenderPayload = BombNetworkPayload & {
+export type BombRenderPayload = {
+  x: number;
+  y: number;
+  explodeAtElapsedMs: number;
   radiusGrid: number;
 };
 
 /** 爆弾設置時に返す結果型 */
 export type BombPlacementResult = {
-  bombId: string;
-  payload: BombNetworkPayload;
+  tempBombId: string;
+  payload: PlaceBombPayload;
 };
 
 type BombManagerOptions = {
@@ -39,7 +41,9 @@
   private myId: string;
   private getElapsedMs: ElapsedMsProvider;
   private bombs = new Map<string, BombController>();
+  private pendingOwnRequestToTempBombId = new Map<string, string>();
   private lastBombPlacedElapsedMs = Number.NEGATIVE_INFINITY;
+  private requestSerial = 0;
 
   constructor({ worldContainer, players, myId, getElapsedMs }: BombManagerOptions) {
     this.worldContainer = worldContainer;
@@ -48,7 +52,7 @@
     this.getElapsedMs = getElapsedMs;
   }
 
-  /** 自プレイヤー位置に爆弾を設置し，生成IDを返す */
+  /** 自プレイヤー位置に爆弾を仮IDで設置し，設置要求を返す */
   public placeBomb(): BombPlacementResult | null {
     const me = this.players[this.myId];
     if (!me || !(me instanceof LocalPlayerController)) return null;
@@ -60,29 +64,37 @@
     }
 
     const position = me.getPosition();
-    const payload: BombNetworkPayload = {
+    const requestId = this.createRequestId(elapsedMs);
+    const payload: PlaceBombPayload = {
+      requestId,
       x: position.x,
       y: position.y,
       explodeAtElapsedMs: elapsedMs + BOMB_FUSE_MS,
     };
-    const bombId = createBombIdFromPayload(payload);
+    const tempBombId = this.createTempBombId(requestId);
 
-    this.upsertBombFromNetwork(bombId, payload);
+    this.pendingOwnRequestToTempBombId.set(requestId, tempBombId);
+    this.upsertBomb(tempBombId, this.toRenderPayload(payload));
     this.lastBombPlacedElapsedMs = elapsedMs;
     return {
-      bombId,
+      tempBombId,
       payload,
     };
   }
 
-  /** 通信ペイロードから指定IDの爆弾を追加または更新する */
-  public upsertBombFromNetwork(bombId: string, payload: BombNetworkPayload): void {
-    const renderPayload: BombRenderPayload = {
-      ...payload,
-      radiusGrid: config.GAME_CONFIG.BOMB_RADIUS_GRID,
-    };
+  /** サーバー確定イベントを反映し，必要なら仮IDから正式IDへ置換する */
+  public applyPlacedBomb(payload: BombPlacedPayload): void {
+    if (payload.ownerId === this.myId) {
+      const tempBombId = this.pendingOwnRequestToTempBombId.get(payload.requestId);
+      if (tempBombId) {
+        this.pendingOwnRequestToTempBombId.delete(payload.requestId);
+        if (tempBombId !== payload.bombId) {
+          this.removeBomb(tempBombId);
+        }
+      }
+    }
 
-    this.upsertBomb(bombId, renderPayload);
+    this.upsertBomb(payload.bombId, this.toRenderPayload(payload));
   }
 
   /** 描画ペイロードで指定IDの爆弾を追加または更新する */
@@ -106,6 +118,7 @@
     this.worldContainer.removeChild(bomb.getDisplayObject());
     bomb.destroy();
     this.bombs.delete(bombId);
+    this.cleanupPendingRequestByTempBombId(bombId);
   }
 
   /** 爆弾状態を更新し終了済みを破棄する */
@@ -126,5 +139,32 @@
   public destroy(): void {
     this.bombs.forEach((bomb) => bomb.destroy());
     this.bombs.clear();
+    this.pendingOwnRequestToTempBombId.clear();
+  }
+
+  private toRenderPayload(payload: { x: number; y: number; explodeAtElapsedMs: number }): BombRenderPayload {
+    return {
+      x: payload.x,
+      y: payload.y,
+      explodeAtElapsedMs: payload.explodeAtElapsedMs,
+      radiusGrid: config.GAME_CONFIG.BOMB_RADIUS_GRID,
+    };
+  }
+
+  private createRequestId(elapsedMs: number): string {
+    this.requestSerial += 1;
+    return `${this.myId}:${elapsedMs}:${this.requestSerial}`;
+  }
+
+  private createTempBombId(requestId: string): string {
+    return `temp:${requestId}`;
+  }
+
+  private cleanupPendingRequestByTempBombId(tempBombId: string): void {
+    this.pendingOwnRequestToTempBombId.forEach((pendingTempBombId, requestId) => {
+      if (pendingTempBombId === tempBombId) {
+        this.pendingOwnRequestToTempBombId.delete(requestId);
+      }
+    });
   }
 }
\ No newline at end of file
diff --git a/apps/server/src/network/handlers/game/registerGameHandlers.ts b/apps/server/src/network/handlers/game/registerGameHandlers.ts
index bc551d4..679430a 100644
--- a/apps/server/src/network/handlers/game/registerGameHandlers.ts
+++ b/apps/server/src/network/handlers/game/registerGameHandlers.ts
@@ -3,7 +3,7 @@
  * ゲーム関連イベントの受信ハンドラを登録する
  */
 import { Server, Socket } from "socket.io";
-import { config, createBombIdFromPayload, protocol } from "@repo/shared";
+import { config, protocol } from "@repo/shared";
 import { readyForGameCoordinator } from "@server/application/coordinators/readyForGameCoordinator";
 import { startGameCoordinator } from "@server/application/coordinators/startGameCoordinator";
 import type {
@@ -16,11 +16,12 @@
 import { movePlayerUseCase } from "@server/domains/game/application/useCases/movePlayerUseCase";
 import { pingUseCase } from "@server/domains/game/application/useCases/pingUseCase";
 import { createCommonHandlerContext } from "@server/network/handlers/CommonHandler";
-import { isBombPlacedPayload, isMovePayload, isPingPayload } from "@server/network/validation/socketPayloadValidators";
+import { isMovePayload, isPingPayload, isPlaceBombPayload } from "@server/network/validation/socketPayloadValidators";
 import { createServerSocketOnBridge } from "@server/network/handlers/socketEventBridge";
 import { createPayloadGuard } from "@server/network/handlers/payloadGuard";
 import { createGameOutputAdapter } from "./createGameOutputAdapter";
 const roomBombDedupTable = new Map<string, Map<string, number>>();
+const roomBombSerialTable = new Map<string, number>();
 
 const cleanupExpiredBombDedup = (roomId: string, nowMs: number) => {
   const roomTable = roomBombDedupTable.get(roomId);
@@ -37,25 +38,31 @@
   }
 };
 
-const shouldBroadcastBombPlaced = (roomId: string, bombId: string, nowMs: number) => {
+const shouldBroadcastBombPlaced = (roomId: string, dedupeKey: string, nowMs: number) => {
   cleanupExpiredBombDedup(roomId, nowMs);
 
   const roomTable = roomBombDedupTable.get(roomId) ?? new Map<string, number>();
-  if (roomTable.has(bombId)) {
+  if (roomTable.has(dedupeKey)) {
     return false;
   }
 
   const ttlMs = config.GAME_CONFIG.BOMB_FUSE_MS + config.GAME_CONFIG.BOMB_DEDUP_EXTRA_TTL_MS;
-  roomTable.set(bombId, nowMs + ttlMs);
+  roomTable.set(dedupeKey, nowMs + ttlMs);
   roomBombDedupTable.set(roomId, roomTable);
   return true;
 };
 
+const issueServerBombId = (roomId: string): string => {
+  const serial = (roomBombSerialTable.get(roomId) ?? 0) + 1;
+  roomBombSerialTable.set(roomId, serial);
+  return `${roomId}:${serial}`;
+};
+
 /** ゲーム受信イベントごとの入力検証関数を保持するテーブル */
 const gamePayloadValidators = {
   [protocol.SocketEvents.PING]: isPingPayload,
   [protocol.SocketEvents.MOVE]: isMovePayload,
-  [protocol.SocketEvents.PLACE_BOMB]: isBombPlacedPayload,
+  [protocol.SocketEvents.PLACE_BOMB]: isPlaceBombPayload,
 } as const;
 
 /** ゲームイベントの購読とユースケース呼び出しを設定する */
@@ -139,11 +146,17 @@
     }
 
     const nowMs = Date.now();
-    const bombId = createBombIdFromPayload(data);
-    if (!shouldBroadcastBombPlaced(roomId, bombId, nowMs)) {
+    const dedupeKey = `${socket.id}:${data.requestId}`;
+    if (!shouldBroadcastBombPlaced(roomId, dedupeKey, nowMs)) {
       return;
     }
 
-    common.emitToRoom(roomId, protocol.SocketEvents.BOMB_PLACED, data);
+    const payload = {
+      ...data,
+      bombId: issueServerBombId(roomId),
+      ownerId: socket.id,
+    };
+
+    common.emitToRoom(roomId, protocol.SocketEvents.BOMB_PLACED, payload);
   });
 };
diff --git a/apps/server/src/network/validation/socketPayloadValidators.ts b/apps/server/src/network/validation/socketPayloadValidators.ts
index ceae7ba..1f950cc 100644
--- a/apps/server/src/network/validation/socketPayloadValidators.ts
+++ b/apps/server/src/network/validation/socketPayloadValidators.ts
@@ -2,7 +2,7 @@
  * socketPayloadValidators
  * ソケット受信ペイロードの型ガードを提供する
  */
-import type { playerTypes, roomTypes, BombPlacedPayload } from "@repo/shared";
+import type { playerTypes, roomTypes, PlaceBombPayload } from "@repo/shared";
 import type { PingPayload } from "@repo/shared";
 
 const isFiniteNumber = (value: unknown): value is number => {
@@ -28,14 +28,16 @@
   return isFiniteNumber(candidate.x) && isFiniteNumber(candidate.y);
 };
 
-/** PLACE_BOMBイベントのペイロードが爆弾情報であるか判定する */
-export const isBombPlacedPayload = (value: unknown): value is BombPlacedPayload => {
+/** PLACE_BOMBイベントのペイロードが爆弾設置要求であるか判定する */
+export const isPlaceBombPayload = (value: unknown): value is PlaceBombPayload => {
   if (typeof value !== "object" || value === null) {
     return false;
   }
 
   const candidate = value as Record<string, unknown>;
   return (
+    isNonEmptyString(candidate.requestId)
+    &&
     isFiniteNumber(candidate.x)
     && isFiniteNumber(candidate.y)
     && isFiniteNumber(candidate.explodeAtElapsedMs)
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index f25e374..95c5a0c 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -31,6 +31,7 @@
 	ServerToClientPayloadOf,
 	CurrentPlayersPayload,
 	BombPlacedPayload,
+	PlaceBombPayload,
 	BombNetworkPayload,
 	GameStartPayload,
 	GameResultPayload,
diff --git a/packages/shared/src/protocol/bombIdentity.ts b/packages/shared/src/protocol/bombIdentity.ts
index ac2dcb0..0c51e66 100644
--- a/packages/shared/src/protocol/bombIdentity.ts
+++ b/packages/shared/src/protocol/bombIdentity.ts
@@ -10,5 +10,5 @@
 
 /** 爆弾ペイロードから同期用IDを生成する */
 export const createBombIdFromPayload = (payload: BombNetworkPayload): string => {
-  return `${payload.x}:${payload.y}:${payload.explodeAtElapsedMs}`;
+  return payload.bombId;
 };
diff --git a/packages/shared/src/protocol/eventPayloads.ts b/packages/shared/src/protocol/eventPayloads.ts
index ede59e7..7d7c6f6 100644
--- a/packages/shared/src/protocol/eventPayloads.ts
+++ b/packages/shared/src/protocol/eventPayloads.ts
@@ -23,6 +23,7 @@
   RemovePlayerPayload,
   GameStartPayload,
   MovePayload,
+  PlaceBombPayload,
   BombPlacedPayload,
   GameResultPayload,
   GameResultRanking,
diff --git a/packages/shared/src/protocol/events.ts b/packages/shared/src/protocol/events.ts
index bdd0978..20329b7 100644
--- a/packages/shared/src/protocol/events.ts
+++ b/packages/shared/src/protocol/events.ts
@@ -22,6 +22,7 @@
   RemovePlayerPayload,
   GameStartPayload,
   MovePayload,
+  PlaceBombPayload,
   BombPlacedPayload,
   PingPayload,
   PongPayload,
diff --git a/packages/shared/src/protocol/maps/gameEventPayloadMap.ts b/packages/shared/src/protocol/maps/gameEventPayloadMap.ts
index 9504411..2e79291 100644
--- a/packages/shared/src/protocol/maps/gameEventPayloadMap.ts
+++ b/packages/shared/src/protocol/maps/gameEventPayloadMap.ts
@@ -11,6 +11,7 @@
   GameStartPayload,
   MovePayload,
   NewPlayerPayload,
+  PlaceBombPayload,
   PingPayload,
   PongPayload,
   RemovePlayerPayload,
@@ -23,7 +24,7 @@
   [SocketEvents.START_GAME]: undefined;
   [SocketEvents.READY_FOR_GAME]: undefined;
   [SocketEvents.MOVE]: MovePayload;
-  [SocketEvents.PLACE_BOMB]: BombPlacedPayload;
+  [SocketEvents.PLACE_BOMB]: PlaceBombPayload;
   [SocketEvents.PING]: PingPayload;
 };
 
diff --git a/packages/shared/src/protocol/payloads/gamePayloads.ts b/packages/shared/src/protocol/payloads/gamePayloads.ts
index 54c8396..7353bd3 100644
--- a/packages/shared/src/protocol/payloads/gamePayloads.ts
+++ b/packages/shared/src/protocol/payloads/gamePayloads.ts
@@ -40,9 +40,16 @@
 /** MOVE イベントで送受信する移動入力情報 */
 export type MovePayload = PlayerMovePayload;
 
-/** PLACE_BOMB / BOMB_PLACED イベントで送受信する爆弾情報 */
-export type BombPlacedPayload = {
+/** PLACE_BOMB イベントで送受信する爆弾設置要求 */
+export type PlaceBombPayload = {
+  requestId: string;
   x: number;
   y: number;
   explodeAtElapsedMs: number;
 };
+
+/** BOMB_PLACED イベントで送受信する爆弾確定情報 */
+export type BombPlacedPayload = PlaceBombPayload & {
+  bombId: string;
+  ownerId: string;
+};