diff --git a/apps/client/src/app.tsx b/apps/client/src/app.tsx
index 6392e30..22010a6 100644
--- a/apps/client/src/app.tsx
+++ b/apps/client/src/app.tsx
@@ -6,7 +6,7 @@
 import { LobbyScene } from "./scenes/LobbyScene";
 import { GameScene } from "./scenes/GameScene";
 
-import { GameState, type Room } from "@repo/shared/src/types/room";
+import { GameState, type Room } from "@repo/shared/src/domains/room/room.type";
 
 export default function App() {
   // 現在シーン状態
diff --git a/apps/client/src/entities/GameMap.ts b/apps/client/src/entities/GameMap.ts
index 90c6cbe..7fdd5cc 100644
--- a/apps/client/src/entities/GameMap.ts
+++ b/apps/client/src/entities/GameMap.ts
@@ -1,7 +1,7 @@
 // apps/client/src/game/map/GameMap.ts (パスは適宜読み替えてください)
 import { Container, Graphics } from "pixi.js";
 import { GAME_CONFIG } from "@repo/shared/src/config/gameConfig";
-import type { MapState, CellUpdate } from "@repo/shared/src/types/map";
+import type { MapState, CellUpdate } from "@repo/shared/src/domains/gridMap/gridMap.type";
 
 // 親クラスを Graphics から Container に変更し、レイヤー管理を可能にする
 export class GameMap extends Container {
diff --git a/apps/client/src/entities/Player.ts b/apps/client/src/entities/Player.ts
index 302b80e..9bc86c6 100644
--- a/apps/client/src/entities/Player.ts
+++ b/apps/client/src/entities/Player.ts
@@ -1,6 +1,6 @@
 import { Graphics } from 'pixi.js';
 import { GAME_CONFIG } from "@repo/shared/src/config/gameConfig";
-import type { PlayerData } from "@repo/shared/src/types/player";
+import type { PlayerData } from "@repo/shared/src/domains/player/player.type";
 
 /**
  * プレイヤーの共通基底クラス（描画と基本データの保持）
diff --git a/apps/client/src/managers/GameManager.ts b/apps/client/src/managers/GameManager.ts
index e62c924..0602885 100644
--- a/apps/client/src/managers/GameManager.ts
+++ b/apps/client/src/managers/GameManager.ts
@@ -1,7 +1,7 @@
 import { Application, Container, Ticker } from "pixi.js";
 import { socketClient } from "../network/SocketClient";
 import { GAME_CONFIG } from "@repo/shared/src/config/gameConfig";
-import type { PlayerData } from "@repo/shared/src/types/player";
+import type { PlayerData } from "@repo/shared/src/domains/player/player.type";
 import { BasePlayer, LocalPlayer, RemotePlayer } from "../entities/Player";
 import { GameMap } from "../entities/GameMap";
 import { MAX_DIST } from "../input/VirtualJoystick";
diff --git a/apps/client/src/network/SocketClient.ts b/apps/client/src/network/SocketClient.ts
index efad8fd..17b2628 100644
--- a/apps/client/src/network/SocketClient.ts
+++ b/apps/client/src/network/SocketClient.ts
@@ -1,8 +1,8 @@
 import { io, Socket } from "socket.io-client";
 import { SocketEvents } from "@repo/shared/src/protocol/events";
-import type { MovePayload, PlayerData } from "@repo/shared/src/types/player";
-import type { CellUpdate } from "@repo/shared/src/types/map";
-import type { Room, JoinRoomPayload } from "@repo/shared/src/types/room";
+import type { MovePayload, PlayerData } from "@repo/shared/src/domains/player/player.type";
+import type { CellUpdate } from "@repo/shared/src/domains/gridMap/gridMap.type";
+import type { Room, JoinRoomPayload } from "@repo/shared/src/domains/room/room.type";
 
 /**
  * サーバー WebSocket 通信管理クラス
diff --git a/apps/client/src/scenes/LobbyScene.tsx b/apps/client/src/scenes/LobbyScene.tsx
index a8b7b3c..f5fcc04 100644
--- a/apps/client/src/scenes/LobbyScene.tsx
+++ b/apps/client/src/scenes/LobbyScene.tsx
@@ -1,4 +1,4 @@
-import type { Room } from "@repo/shared/src/types/room";
+import type { Room } from "@repo/shared/src/domains/room/room.type";
 
 type Props = {
   room: Room | null;
diff --git a/apps/client/src/scenes/TitleScene.tsx b/apps/client/src/scenes/TitleScene.tsx
index bf8b5f1..7d34f71 100644
--- a/apps/client/src/scenes/TitleScene.tsx
+++ b/apps/client/src/scenes/TitleScene.tsx
@@ -1,6 +1,6 @@
 import { useState } from "react";
 // ルーム参加時送信ペイロード型
-import type { JoinRoomPayload } from "@repo/shared/src/types/room";
+import type { JoinRoomPayload } from "@repo/shared/src/domains/room/room.type";
 
 type Props = {
   // 入室実行時呼び出しコールバック
diff --git a/apps/server/src/entities/Player.ts b/apps/server/src/entities/Player.ts
index cac7401..edc7976 100644
--- a/apps/server/src/entities/Player.ts
+++ b/apps/server/src/entities/Player.ts
@@ -1,4 +1,4 @@
-import type { PlayerData } from "@repo/shared/src/types/player";
+import type { PlayerData } from "@repo/shared/src/domains/player/player.type";
 import { GAME_CONFIG } from "@repo/shared/src/config/gameConfig";
 
 // サーバー側保持プレイヤー状態モデル
diff --git a/apps/server/src/handlers/GameHandler.ts b/apps/server/src/handlers/GameHandler.ts
index a555402..6477919 100644
--- a/apps/server/src/handlers/GameHandler.ts
+++ b/apps/server/src/handlers/GameHandler.ts
@@ -2,8 +2,8 @@
 import { GameManager } from "../managers/GameManager.js";
 import { RoomManager } from "../managers/RoomManager.js";
 import { SocketEvents } from "@repo/shared/src/protocol/events";
-import { RoomStatus } from "@repo/shared/src/types/room";
-import type { MovePayload } from "@repo/shared/src/types/player";
+import { RoomStatus } from "@repo/shared/src/domains/room/room.type";
+import type { MovePayload } from "@repo/shared/src/domains/player/player.type";
 
 export const registerGameHandlers = (io: Server, socket: Socket, gameManager: GameManager, roomManager: RoomManager) => {
   
@@ -15,7 +15,7 @@
       room.status = RoomStatus.PLAYING;
       
       // 同ルーム全プレイヤーのゲーム管理登録
-      room.players.forEach(p => {
+      room.players.forEach((p: { id: string }) => {
         gameManager.addPlayer(p.id);
       });
 
diff --git a/apps/server/src/handlers/RoomHandler.ts b/apps/server/src/handlers/RoomHandler.ts
index 6a239a3..e3f0e23 100644
--- a/apps/server/src/handlers/RoomHandler.ts
+++ b/apps/server/src/handlers/RoomHandler.ts
@@ -1,7 +1,7 @@
 import { Server, Socket } from "socket.io";
 import { RoomManager } from "../managers/RoomManager.js";
 import { SocketEvents } from "@repo/shared/src/protocol/events";
-import type { JoinRoomPayload } from "@repo/shared/src/types/room";
+import type { JoinRoomPayload } from "@repo/shared/src/domains/room/room.type";
 
 export const registerRoomHandlers = (io: Server, socket: Socket, roomManager: RoomManager) => {
   
diff --git a/apps/server/src/managers/RoomManager.ts b/apps/server/src/managers/RoomManager.ts
index 3229016..3be6e62 100644
--- a/apps/server/src/managers/RoomManager.ts
+++ b/apps/server/src/managers/RoomManager.ts
@@ -1,4 +1,4 @@
-import { Room, RoomStatus, RoomMember } from "@repo/shared/src/types/room";
+import { Room, RoomStatus, RoomMember } from "@repo/shared/src/domains/room/room.type";
 import { GAME_CONFIG } from "@repo/shared/src/config/gameConfig";
 
 export class RoomManager {
diff --git "a/docs/01_Env/ENV_01_\347\222\260\345\242\203\346\247\213\347\257\211\343\203\273\346\212\200\350\241\223\343\202\271\343\202\277\343\203\203\343\202\257.txt" "b/docs/01_Env/ENV_01_\347\222\260\345\242\203\346\247\213\347\257\211\343\203\273\346\212\200\350\241\223\343\202\271\343\202\277\343\203\203\343\202\257.txt"
index fb7b4b7..ef06a45 100644
--- "a/docs/01_Env/ENV_01_\347\222\260\345\242\203\346\247\213\347\257\211\343\203\273\346\212\200\350\241\223\343\202\271\343\202\277\343\203\203\343\202\257.txt"
+++ "b/docs/01_Env/ENV_01_\347\222\260\345\242\203\346\247\213\347\257\211\343\203\273\346\212\200\350\241\223\343\202\271\343\202\277\343\203\203\343\202\257.txt"
@@ -66,13 +66,15 @@
     └── packages/
         └── shared/           # 【最重要】「真実」の定義場所（型、定数、純粋ロジック）
             ├── src/
-            │   ├── config/     # 共通定数（gameConfig.ts）
-            │   ├── logic/      # 共通ロジック（gridMap.ts）
-            │   ├── protocol/   # 通信イベント定義（events.ts）
-            │   ├── types/      # 型定義（map.ts, payloads.ts, player.ts, room.ts）
+            │   ├── config/     # 共通定数 (gameConfig.ts)
+            │   ├── domains/    # ドメイン別ロジック・型定義
+            │   │   ├── gridMap/# マップ・グリッド関連 (gridMap.logic.ts, gridMap.type.ts)
+            │   │   ├── player/ # プレイヤー関連 (player.type.ts)
+            │   │   └── room/   # ルーム・進行管理 (room.type.ts)
+            │   ├── protocol/   # 通信イベント・バイナリ定義 (events.ts)
             │   └── index.ts    # エントリーポイント (tsupビルド対象)
             ├── tsup.config.ts  # ビルド設定
-            └── package.json
+            └── package.json    # パッケージ定義
 
         ※ shared は client/server 両方から import して使用する．
 
diff --git a/packages/shared/src/domains/gridMap/gridMap.logic.ts b/packages/shared/src/domains/gridMap/gridMap.logic.ts
new file mode 100644
index 0000000..bb28b3f
--- /dev/null
+++ b/packages/shared/src/domains/gridMap/gridMap.logic.ts
@@ -0,0 +1,20 @@
+import { GAME_CONFIG } from "../../config/gameConfig";
+
+/**
+ * ピクセル座標からグリッドの1次元配列インデックスを取得する（中心点判定）
+ */
+export function getGridIndexFromPosition(x: number, y: number): number | null {
+  const { GRID_CELL_SIZE, GRID_COLS, GRID_ROWS } = GAME_CONFIG;
+
+  // 座標がどのマス（列・行）に属するか計算
+  const col = Math.floor(x / GRID_CELL_SIZE);
+  const row = Math.floor(y / GRID_CELL_SIZE);
+
+  // マップ外の場合は null を返す
+  if (col < 0 || col >= GRID_COLS || row < 0 || row >= GRID_ROWS) {
+    return null;
+  }
+
+  // 1次元配列のインデックスに変換 (row * 幅 + col)
+  return row * GRID_COLS + col;
+}
\ No newline at end of file
diff --git a/packages/shared/src/domains/gridMap/gridMap.type.ts b/packages/shared/src/domains/gridMap/gridMap.type.ts
new file mode 100644
index 0000000..d85090e
--- /dev/null
+++ b/packages/shared/src/domains/gridMap/gridMap.type.ts
@@ -0,0 +1,8 @@
+export interface MapState {
+  gridColors: number[];
+}
+
+export interface CellUpdate {
+  index: number;
+  teamId: number;
+}
\ No newline at end of file
diff --git a/packages/shared/src/domains/player/player.type.ts b/packages/shared/src/domains/player/player.type.ts
new file mode 100644
index 0000000..ff22892
--- /dev/null
+++ b/packages/shared/src/domains/player/player.type.ts
@@ -0,0 +1,13 @@
+// クライアント・サーバー間共有プレイヤー基本情報型
+export interface PlayerData {
+  id: string;
+  x: number;
+  y: number;
+  teamId: number;   // 0〜3 のチームID
+}
+
+// 移動イベント送信ペイロード型
+export interface MovePayload {
+  x: number;
+  y: number;
+}
\ No newline at end of file
diff --git a/packages/shared/src/domains/room/room.type.ts b/packages/shared/src/domains/room/room.type.ts
new file mode 100644
index 0000000..9f88187
--- /dev/null
+++ b/packages/shared/src/domains/room/room.type.ts
@@ -0,0 +1,38 @@
+// クライアント画面遷移利用ゲーム状態型
+export const GameState = {
+  TITLE: 'title',
+  LOBBY: 'lobby',
+  PLAYING: 'playing',
+} as const;
+export type GameState = typeof GameState[keyof typeof GameState];
+
+// ルーム進行フェーズ状態型
+export const RoomStatus = {
+  WAITING: 'waiting',
+  PLAYING: 'playing',
+  RESULT: 'result',
+} as const;
+export type RoomStatus = typeof RoomStatus[keyof typeof RoomStatus];
+
+// ルーム所属プレイヤー情報型
+export interface RoomMember {
+  id: string;
+  name: string;
+  isOwner: boolean;
+  isReady: boolean;
+}
+
+// ルーム全体状態データ構造型
+export interface Room {
+  roomId: string;
+  ownerId: string;
+  players: RoomMember[];
+  status: RoomStatus;
+  maxPlayers: number;
+}
+
+// ルーム参加時送信ペイロード型
+export interface JoinRoomPayload {
+  roomId: string;
+  playerName: string;
+}
\ No newline at end of file
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index e1bba2b..e290030 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -1,7 +1,7 @@
 // shared パッケージ公開 API
-export * from './config/gameConfig';
+export * from "./domains/gridMap/gridMap.type";
+export * from "./domains/gridMap/gridMap.logic";
+export * from "./domains/player/player.type";
+export * from "./domains/room/room.type";
 export * from "./protocol/events";
-export * from './types/map';
-export * from './types/payloads';
-export * from './types/player';
-export * from './types/room';
\ No newline at end of file
+export * from "./config/gameConfig";
\ No newline at end of file
diff --git a/packages/shared/src/logic/gridMap.ts b/packages/shared/src/logic/gridMap.ts
deleted file mode 100644
index 10dd3b5..0000000
--- a/packages/shared/src/logic/gridMap.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-import { GAME_CONFIG } from "../config/gameConfig";
-
-/**
- * ピクセル座標からグリッドの1次元配列インデックスを取得する（中心点判定）
- */
-export function getGridIndexFromPosition(x: number, y: number): number | null {
-  const { GRID_CELL_SIZE, GRID_COLS, GRID_ROWS } = GAME_CONFIG;
-
-  // 座標がどのマス（列・行）に属するか計算
-  const col = Math.floor(x / GRID_CELL_SIZE);
-  const row = Math.floor(y / GRID_CELL_SIZE);
-
-  // マップ外の場合は null を返す
-  if (col < 0 || col >= GRID_COLS || row < 0 || row >= GRID_ROWS) {
-    return null;
-  }
-
-  // 1次元配列のインデックスに変換 (row * 幅 + col)
-  return row * GRID_COLS + col;
-}
\ No newline at end of file
diff --git a/packages/shared/src/types/map.ts b/packages/shared/src/types/map.ts
deleted file mode 100644
index d85090e..0000000
--- a/packages/shared/src/types/map.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-export interface MapState {
-  gridColors: number[];
-}
-
-export interface CellUpdate {
-  index: number;
-  teamId: number;
-}
\ No newline at end of file
diff --git a/packages/shared/src/types/player.ts b/packages/shared/src/types/player.ts
deleted file mode 100644
index ff22892..0000000
--- a/packages/shared/src/types/player.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-// クライアント・サーバー間共有プレイヤー基本情報型
-export interface PlayerData {
-  id: string;
-  x: number;
-  y: number;
-  teamId: number;   // 0〜3 のチームID
-}
-
-// 移動イベント送信ペイロード型
-export interface MovePayload {
-  x: number;
-  y: number;
-}
\ No newline at end of file
diff --git a/packages/shared/src/types/room.ts b/packages/shared/src/types/room.ts
deleted file mode 100644
index 9f88187..0000000
--- a/packages/shared/src/types/room.ts
+++ /dev/null
@@ -1,38 +0,0 @@
-// クライアント画面遷移利用ゲーム状態型
-export const GameState = {
-  TITLE: 'title',
-  LOBBY: 'lobby',
-  PLAYING: 'playing',
-} as const;
-export type GameState = typeof GameState[keyof typeof GameState];
-
-// ルーム進行フェーズ状態型
-export const RoomStatus = {
-  WAITING: 'waiting',
-  PLAYING: 'playing',
-  RESULT: 'result',
-} as const;
-export type RoomStatus = typeof RoomStatus[keyof typeof RoomStatus];
-
-// ルーム所属プレイヤー情報型
-export interface RoomMember {
-  id: string;
-  name: string;
-  isOwner: boolean;
-  isReady: boolean;
-}
-
-// ルーム全体状態データ構造型
-export interface Room {
-  roomId: string;
-  ownerId: string;
-  players: RoomMember[];
-  status: RoomStatus;
-  maxPlayers: number;
-}
-
-// ルーム参加時送信ペイロード型
-export interface JoinRoomPayload {
-  roomId: string;
-  playerName: string;
-}
\ No newline at end of file