diff --git a/apps/server/src/application/coordinators/disconnectCoordinator.ts b/apps/server/src/application/coordinators/disconnectCoordinator.ts
index f6c899f..a830dda 100644
--- a/apps/server/src/application/coordinators/disconnectCoordinator.ts
+++ b/apps/server/src/application/coordinators/disconnectCoordinator.ts
@@ -3,7 +3,6 @@
  * DISCONNECTイベントの調停を行い，ゲーム離脱処理とルーム離脱処理を順序実行する
  */
 import {
-  type BombCleanupPort,
   type DisconnectPlayerPort,
   type GameOutputPort,
 } from "@server/domains/game/application/ports/gameUseCasePorts";
@@ -20,7 +19,6 @@
 export type DisconnectCoordinatorParams = {
   socketId: string;
   gameManager: DisconnectPlayerPort;
-  bombState: BombCleanupPort;
   roomManager: DisconnectRoomPort & FindRoomByPlayerPort & FindRoomByIdPort;
   gameOutput: Pick<GameOutputPort, "publishPlayerRemovedToRoom">;
   roomOutput: Pick<RoomOutputPort, "publishRoomUpdateToRoom">;
@@ -30,7 +28,6 @@
 export const disconnectCoordinator = ({
   socketId,
   gameManager,
-  bombState,
   roomManager,
   gameOutput,
   roomOutput,
@@ -49,8 +46,4 @@
     socketId,
     output: roomOutput,
   });
-
-  if (roomId && !roomManager.getRoomById(roomId)) {
-    bombState.clearBombRoomState(roomId, "room-deleted");
-  }
 };
diff --git a/apps/server/src/application/coordinators/startGameCoordinator.ts b/apps/server/src/application/coordinators/startGameCoordinator.ts
index 049dd23..c69f378 100644
--- a/apps/server/src/application/coordinators/startGameCoordinator.ts
+++ b/apps/server/src/application/coordinators/startGameCoordinator.ts
@@ -3,7 +3,6 @@
  * START_GAMEイベントの調停を行い，ルーム状態更新とゲーム開始処理を橋渡しする
  */
 import {
-  type BombCleanupPort,
   type GameOutputPort,
   type StartGamePort,
 } from "@server/domains/game/application/ports/gameUseCasePorts";
@@ -19,7 +18,6 @@
 type StartGameCoordinatorParams = {
   ownerId: string;
   gameManager: StartGamePort;
-  bombState: BombCleanupPort;
   roomManager: FindRoomByOwnerPort & RoomPhaseTransitionPort;
   output: Pick<
     GameOutputPort,
@@ -35,7 +33,6 @@
 export const startGameCoordinator = ({
   ownerId,
   gameManager,
-  bombState,
   roomManager,
   output,
 }: StartGameCoordinatorParams) => {
@@ -86,7 +83,6 @@
     gameManager,
     onGameEnd: () => {
       roomManager.markRoomWaiting(updatedRoom.roomId);
-      bombState.clearBombRoomState(updatedRoom.roomId, "game-ended");
     },
     output,
   });
diff --git a/apps/server/src/domains/game/GameManager.ts b/apps/server/src/domains/game/GameManager.ts
index 389f85c..277878a 100644
--- a/apps/server/src/domains/game/GameManager.ts
+++ b/apps/server/src/domains/game/GameManager.ts
@@ -59,4 +59,14 @@
   getRoomPlayers(roomId: string): Player[] {
     return this.lifecycleService.getRoomPlayers(roomId);
   }
+
+  // 爆弾設置イベントを配信すべきか判定し，配信時は重複排除状態を更新する
+  shouldBroadcastBombPlaced(roomId: string, dedupeKey: string, nowMs: number): boolean {
+    return this.lifecycleService.shouldBroadcastBombPlaced(roomId, dedupeKey, nowMs);
+  }
+
+  // ルーム単位の連番からサーバー採番の爆弾IDを生成する
+  issueServerBombId(roomId: string): string {
+    return this.lifecycleService.issueServerBombId(roomId);
+  }
 }
\ No newline at end of file
diff --git a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
index 7b21bed..d5850f5 100644
--- a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
+++ b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
@@ -2,7 +2,6 @@
  * gameUseCasePorts
  * ゲーム系ユースケースが利用する入力ポートと出力ポートの契約を定義する
  */
-import type { BombRoomStateClearReason } from "@server/domains/game/entities/bomb/BombRoomStateStore";
 import type {
   BombPlacedPayload,
   gameTypes,
@@ -71,14 +70,6 @@
   issueServerBombId(roomId: string): string;
 }
 
-/** 爆弾状態破棄ユースケースが利用する入力ポート */
-export interface BombCleanupPort {
-  clearBombRoomState(roomId: string, reason: BombRoomStateClearReason): void;
-}
-
-/** 爆弾状態の参照更新と破棄を扱う統合入力ポート */
-export interface BombStatePort extends BombPlacementPort, BombCleanupPort {}
-
 /** 爆弾設置ユースケースの入力値 */
 export type PlaceBombInput = {
   socketId: string;
diff --git a/apps/server/src/domains/game/application/services/GameRoomSession.ts b/apps/server/src/domains/game/application/services/GameRoomSession.ts
index 75d1b06..959fe41 100644
--- a/apps/server/src/domains/game/application/services/GameRoomSession.ts
+++ b/apps/server/src/domains/game/application/services/GameRoomSession.ts
@@ -12,6 +12,7 @@
 import { GameLoop } from "../../loop/GameLoop";
 import { Player } from "../../entities/player/Player.js";
 import { MapStore } from "../../entities/map/MapStore";
+import { BombRoomStateStore } from "../../entities/bomb/BombRoomStateStore";
 import { createSpawnedPlayer } from "../../entities/player/playerSpawn.js";
 import {
   isValidPosition,
@@ -24,6 +25,7 @@
 export class GameRoomSession {
   private players: Map<string, Player>;
   private mapStore: MapStore;
+  private bombStateStore: BombRoomStateStore;
   private gameLoop: GameLoop | null = null;
   private startTime: number | undefined;
 
@@ -33,6 +35,7 @@
   ) {
     this.players = new Map();
     this.mapStore = new MapStore();
+    this.bombStateStore = new BombRoomStateStore();
 
     playerIds.forEach((playerId) => {
       // 現在のプレイヤー構成から人数が最も少ないチームを算出する
@@ -114,6 +117,14 @@
     return this.players.has(id);
   }
 
+  public shouldBroadcastBombPlaced(dedupeKey: string, nowMs: number): boolean {
+    return this.bombStateStore.shouldBroadcastBombPlaced(dedupeKey, nowMs);
+  }
+
+  public issueServerBombId(): string {
+    return this.bombStateStore.issueServerBombId(this.roomId);
+  }
+
   public dispose(): void {
     if (this.gameLoop) {
       this.gameLoop.stop();
diff --git a/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts b/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
index 748d349..0d4517a 100644
--- a/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
+++ b/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
@@ -28,6 +28,19 @@
     return this.sessions.get(roomId)?.getPlayers() ?? [];
   }
 
+  public shouldBroadcastBombPlaced(roomId: string, dedupeKey: string, nowMs: number): boolean {
+    return this.sessions.get(roomId)?.shouldBroadcastBombPlaced(dedupeKey, nowMs) ?? false;
+  }
+
+  public issueServerBombId(roomId: string): string {
+    const session = this.sessions.get(roomId);
+    if (!session) {
+      throw new Error(`Game session not found for roomId: ${roomId}`);
+    }
+
+    return session.issueServerBombId();
+  }
+
   public startRoomSession(
     roomId: string,
     playerIds: string[],
diff --git a/apps/server/src/domains/game/entities/bomb/BombRoomStateStore.ts b/apps/server/src/domains/game/entities/bomb/BombRoomStateStore.ts
index cd4e006..d217a95 100644
--- a/apps/server/src/domains/game/entities/bomb/BombRoomStateStore.ts
+++ b/apps/server/src/domains/game/entities/bomb/BombRoomStateStore.ts
@@ -4,65 +4,35 @@
  */
 import { config } from "@repo/shared";
 
-/** 爆弾状態破棄理由の識別子 */
-export type BombRoomStateClearReason = "game-ended" | "room-deleted";
-
 /** ルーム単位の爆弾重複排除状態と採番状態を保持するストア */
 export class BombRoomStateStore {
-  private roomBombDedupTable = new Map<string, Map<string, number>>();
-  private roomBombSerialTable = new Map<string, number>();
-  private isBombRoomStateDebugEnabled = process.env.NODE_ENV !== "production";
+  private bombDedupTable = new Map<string, number>();
+  private bombSerial = 0;
 
   /** 爆弾設置イベントを配信すべきか判定し，配信時は重複排除状態を更新する */
-  public shouldBroadcastBombPlaced(roomId: string, dedupeKey: string, nowMs: number): boolean {
-    this.cleanupExpiredBombDedup(roomId, nowMs);
+  public shouldBroadcastBombPlaced(dedupeKey: string, nowMs: number): boolean {
+    this.cleanupExpiredBombDedup(nowMs);
 
-    const roomTable = this.roomBombDedupTable.get(roomId) ?? new Map<string, number>();
-    if (roomTable.has(dedupeKey)) {
+    if (this.bombDedupTable.has(dedupeKey)) {
       return false;
     }
 
     const ttlMs = config.GAME_CONFIG.BOMB_FUSE_MS + config.GAME_CONFIG.BOMB_DEDUP_EXTRA_TTL_MS;
-    roomTable.set(dedupeKey, nowMs + ttlMs);
-    this.roomBombDedupTable.set(roomId, roomTable);
+    this.bombDedupTable.set(dedupeKey, nowMs + ttlMs);
     return true;
   }
 
-  /** ルーム単位の連番からサーバー採番の爆弾IDを生成する */
+  /** セッション単位の連番からサーバー採番の爆弾IDを生成する */
   public issueServerBombId(roomId: string): string {
-    const serial = (this.roomBombSerialTable.get(roomId) ?? 0) + 1;
-    this.roomBombSerialTable.set(roomId, serial);
-    return `${roomId}:${serial}`;
+    this.bombSerial += 1;
+    return `${roomId}:${this.bombSerial}`;
   }
 
-  /** 指定ルームの爆弾採番状態と重複排除状態を破棄する */
-  public clearBombRoomState(roomId: string, reason: BombRoomStateClearReason): void {
-    const hadDedupState = this.roomBombDedupTable.delete(roomId);
-    const hadSerialState = this.roomBombSerialTable.delete(roomId);
-
-    if (!this.isBombRoomStateDebugEnabled) {
-      return;
-    }
-
-    console.debug(
-      `[BombState] cleared room=${roomId} reason=${reason} dedup=${hadDedupState} serial=${hadSerialState}`
-    );
-  }
-
-  private cleanupExpiredBombDedup(roomId: string, nowMs: number): void {
-    const roomTable = this.roomBombDedupTable.get(roomId);
-    if (!roomTable) {
-      return;
-    }
-
-    roomTable.forEach((expiresAtMs, dedupeKey) => {
+  private cleanupExpiredBombDedup(nowMs: number): void {
+    this.bombDedupTable.forEach((expiresAtMs, dedupeKey) => {
       if (expiresAtMs <= nowMs) {
-        roomTable.delete(dedupeKey);
+        this.bombDedupTable.delete(dedupeKey);
       }
     });
-
-    if (roomTable.size === 0) {
-      this.roomBombDedupTable.delete(roomId);
-    }
   }
 }
diff --git a/apps/server/src/network/SocketManager.ts b/apps/server/src/network/SocketManager.ts
index 6ba5c30..279a30c 100644
--- a/apps/server/src/network/SocketManager.ts
+++ b/apps/server/src/network/SocketManager.ts
@@ -4,7 +4,6 @@
  */
 import { Server } from "socket.io";
 import type {
-  SocketConnectionBombPort,
   SocketConnectionManagerBundle,
   SocketConnectionGamePort,
   SocketConnectionRoomPort,
@@ -19,13 +18,11 @@
   constructor(
     io: Server,
     gameManager: SocketConnectionGamePort,
-    bombState: SocketConnectionBombPort,
     roomManager: SocketConnectionRoomPort
   ) {
     this.io = io;
     this.managers = {
       gameManager,
-      bombState,
       roomManager,
     };
   }
diff --git a/apps/server/src/network/bootstrap/boot.ts b/apps/server/src/network/bootstrap/boot.ts
index 414e6eb..29ba1ff 100644
--- a/apps/server/src/network/bootstrap/boot.ts
+++ b/apps/server/src/network/bootstrap/boot.ts
@@ -4,7 +4,6 @@
  */
 import type { Server as HttpServer } from "http";
 import { GameManager } from "@server/domains/game/GameManager";
-import { BombRoomStateStore } from "@server/domains/game/entities/bomb/BombRoomStateStore";
 import { RoomManager } from "@server/domains/room/RoomManager";
 import { SocketManager } from "../SocketManager";
 import { createIo } from "./createIo";
@@ -14,9 +13,8 @@
   // ネットワーク層とドメイン層の依存を構築する
   const io = createIo(httpServer);
   const gameManager = new GameManager();
-  const bombState = new BombRoomStateStore();
   const roomManager = new RoomManager();
-  const socketManager = new SocketManager(io, gameManager, bombState, roomManager);
+  const socketManager = new SocketManager(io, gameManager, roomManager);
 
   socketManager.initialize();
 };
diff --git a/apps/server/src/network/handlers/game/registerGameHandlers.ts b/apps/server/src/network/handlers/game/registerGameHandlers.ts
index d1e0fa6..525b6d9 100644
--- a/apps/server/src/network/handlers/game/registerGameHandlers.ts
+++ b/apps/server/src/network/handlers/game/registerGameHandlers.ts
@@ -13,7 +13,6 @@
 } from "@server/domains/room/application/ports/roomUseCasePorts";
 import type {
   BombPlacementPort,
-  BombCleanupPort,
   MovePlayerPort,
   ReadyForGamePort,
   StartGamePort,
@@ -38,8 +37,7 @@
 export const registerGameHandlers = (
   io: Server,
   socket: Socket,
-  gameManager: StartGamePort & ReadyForGamePort & MovePlayerPort,
-  bombState: BombPlacementPort & BombCleanupPort,
+  gameManager: StartGamePort & ReadyForGamePort & MovePlayerPort & BombPlacementPort,
   roomManager: FindRoomByOwnerPort & FindRoomByPlayerPort & RoomPhaseTransitionPort
 ) => {
   const common = createCommonHandlerContext(io, socket);
@@ -75,7 +73,6 @@
     startGameCoordinator({
       ownerId: socket.id,
       gameManager,
-      bombState,
       roomManager,
       output: gameOutputAdapter,
     });
@@ -112,7 +109,7 @@
 
     placeBombUseCase({
       roomResolver: roomManager,
-      bombStore: bombState,
+      bombStore: gameManager,
       input: {
         socketId: socket.id,
         payload: data,
diff --git a/apps/server/src/network/handlers/registerConnectionHandlers.ts b/apps/server/src/network/handlers/registerConnectionHandlers.ts
index 5701b69..66850a8 100644
--- a/apps/server/src/network/handlers/registerConnectionHandlers.ts
+++ b/apps/server/src/network/handlers/registerConnectionHandlers.ts
@@ -19,7 +19,6 @@
 export const registerConnectionHandlers = ({
   io,
   gameManager,
-  bombState,
   roomManager,
 }: RegisterConnectionHandlersParams) => {
   const gameDisconnectOutputAdapter = createGameDisconnectOutputAdapter(io);
@@ -34,7 +33,7 @@
     });
 
     registerRoomHandlers(io, socket, roomManager);
-    registerGameHandlers(io, socket, gameManager, bombState, roomManager);
+    registerGameHandlers(io, socket, gameManager, roomManager);
 
     socket.on(protocol.SocketEvents.DISCONNECT, () => {
       // 切断ログ記録後にドメイン別の後処理を実行する
@@ -47,7 +46,6 @@
       disconnectCoordinator({
         socketId: socket.id,
         gameManager,
-        bombState,
         roomManager,
         gameOutput: gameDisconnectOutputAdapter,
         roomOutput: roomDisconnectOutputAdapter,
diff --git a/apps/server/src/network/types/connectionPorts.ts b/apps/server/src/network/types/connectionPorts.ts
index 7e872b7..c3713a4 100644
--- a/apps/server/src/network/types/connectionPorts.ts
+++ b/apps/server/src/network/types/connectionPorts.ts
@@ -4,12 +4,12 @@
  */
 import type { Server } from "socket.io";
 import type {
+  BombPlacementPort,
   DisconnectPlayerPort,
   MovePlayerPort,
   ReadyForGamePort,
   StartGamePort,
 } from "@server/domains/game/application/ports/gameUseCasePorts";
-import type { BombStatePort } from "@server/domains/game/application/ports/gameUseCasePorts";
 import type {
   DisconnectRoomPort,
   FindRoomByOwnerPort,
@@ -24,7 +24,8 @@
 export type ConnectionGamePort =
   & StartGamePort
   & ReadyForGamePort
-  & MovePlayerPort;
+  & MovePlayerPort
+  & BombPlacementPort;
 
 /** 接続時のルーム処理で利用する入力ポート集合 */
 export type ConnectionRoomPort =
@@ -38,9 +39,6 @@
   & ConnectionGamePort
   & DisconnectPlayerPort;
 
-/** ソケット接続全体で利用する爆弾状態ポート集合 */
-export type SocketConnectionBombPort = BombStatePort;
-
 /** ソケット接続全体で利用するルーム管理ポート集合 */
 export type SocketConnectionRoomPort =
   & ConnectionRoomPort
@@ -50,7 +48,6 @@
 /** ソケット接続ハンドラで受け取るマネージャ依存の束 */
 export type SocketConnectionManagerBundle = {
   gameManager: SocketConnectionGamePort;
-  bombState: SocketConnectionBombPort;
   roomManager: SocketConnectionRoomPort;
 };