diff --git a/backend/package-lock.json b/backend/package-lock.json
index f531eeea5..44ae1d2c4 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -37,6 +37,7 @@
         "jest": "29.5.0",
         "prettier": "^2.3.2",
         "prisma": "^4.12.0",
+        "socket.io-client": "^4.6.1",
         "source-map-support": "^0.5.20",
         "supertest": "^6.1.3",
         "ts-jest": "29.0.5",
@@ -3681,6 +3682,19 @@
         "node": ">=10.0.0"
       }
     },
+    "node_modules/engine.io-client": {
+      "version": "6.4.0",
+      "resolved": "https://registry.npmjs.org/engine.io-client/-/engine.io-client-6.4.0.tgz",
+      "integrity": "sha512-GyKPDyoEha+XZ7iEqam49vz6auPnNJ9ZBfy89f+rMMas8AuiMWOZ9PVzu8xb9ZC6rafUqiGHSCfu22ih66E+1g==",
+      "dev": true,
+      "dependencies": {
+        "@socket.io/component-emitter": "~3.1.0",
+        "debug": "~4.3.1",
+        "engine.io-parser": "~5.0.3",
+        "ws": "~8.11.0",
+        "xmlhttprequest-ssl": "~2.0.0"
+      }
+    },
     "node_modules/engine.io-parser": {
       "version": "5.0.6",
       "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-5.0.6.tgz",
@@ -7898,6 +7912,21 @@
         "ws": "~8.11.0"
       }
     },
+    "node_modules/socket.io-client": {
+      "version": "4.6.1",
+      "resolved": "https://registry.npmjs.org/socket.io-client/-/socket.io-client-4.6.1.tgz",
+      "integrity": "sha512-5UswCV6hpaRsNg5kkEHVcbBIXEYoVbMQaHJBXJCyEQ+CiFPV1NIOY0XOFWG4XR4GZcB8Kn6AsRs/9cy9TbqVMQ==",
+      "dev": true,
+      "dependencies": {
+        "@socket.io/component-emitter": "~3.1.0",
+        "debug": "~4.3.2",
+        "engine.io-client": "~6.4.0",
+        "socket.io-parser": "~4.2.1"
+      },
+      "engines": {
+        "node": ">=10.0.0"
+      }
+    },
     "node_modules/socket.io-parser": {
       "version": "4.2.3",
       "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.2.3.tgz",
@@ -9040,6 +9069,15 @@
         }
       }
     },
+    "node_modules/xmlhttprequest-ssl": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/xmlhttprequest-ssl/-/xmlhttprequest-ssl-2.0.0.tgz",
+      "integrity": "sha512-QKxVRxiRACQcVuQEYFsI1hhkrMlrXHPegbbd1yn9UHOmRxY+si12nQYzri3vbzt8VdTTRviqcKxcyllFas5z2A==",
+      "dev": true,
+      "engines": {
+        "node": ">=0.4.0"
+      }
+    },
     "node_modules/xtend": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
diff --git a/backend/package.json b/backend/package.json
index 67b5632b0..dde0bb03a 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -50,6 +50,7 @@
     "jest": "29.5.0",
     "prettier": "^2.3.2",
     "prisma": "^4.12.0",
+    "socket.io-client": "^4.6.1",
     "source-map-support": "^0.5.20",
     "supertest": "^6.1.3",
     "ts-jest": "29.0.5",
diff --git a/backend/prisma/seed.ts b/backend/prisma/seed.ts
index 3f253b8b5..d6cbe9c71 100644
--- a/backend/prisma/seed.ts
+++ b/backend/prisma/seed.ts
@@ -25,12 +25,8 @@ async function main() {
       hashedPassword: 'piyopiyo',
     },
   });
-  const room = await prisma.chatRoom.upsert({
-    where: {
-      roomName: 'hogeRoom',
-    },
-    update: {},
-    create: {
+  const room = await prisma.chatRoom.create({
+    data: {
       roomName: 'hogeRoom',
     },
   });
diff --git a/backend/src/app.module.ts b/backend/src/app.module.ts
index d69ed6a0b..7b2ca6f3f 100644
--- a/backend/src/app.module.ts
+++ b/backend/src/app.module.ts
@@ -7,9 +7,16 @@ import { EventsGateway } from './events/events.gateway';
 import { PostMessageModule } from './post-message/post-message.module';
 import { PrismaModule } from './prisma/prisma.module';
 import { UserModule } from './user/user.module';
+import { ChatModule } from './chat/chat.module';
 
 @Module({
-  imports: [PrismaModule, PostMessageModule, ConfigModule, UserModule],
+  imports: [
+    PrismaModule,
+    PostMessageModule,
+    ConfigModule,
+    UserModule,
+    ChatModule,
+  ],
   controllers: [AppController],
   providers: [AppService, EventsGateway],
 })
diff --git a/backend/src/chat/chat.controller.spec.ts b/backend/src/chat/chat.controller.spec.ts
new file mode 100644
index 000000000..3f9e47fe3
--- /dev/null
+++ b/backend/src/chat/chat.controller.spec.ts
@@ -0,0 +1,19 @@
+import { Test, TestingModule } from '@nestjs/testing';
+
+import { ChatController } from './chat.controller';
+
+describe('ChatController', () => {
+  let controller: ChatController;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      controllers: [ChatController],
+    }).compile();
+
+    controller = module.get<ChatController>(ChatController);
+  });
+
+  test('should be defined', () => {
+    expect(controller).toBeDefined();
+  });
+});
diff --git a/backend/src/chat/chat.controller.ts b/backend/src/chat/chat.controller.ts
new file mode 100644
index 000000000..d71b71a9a
--- /dev/null
+++ b/backend/src/chat/chat.controller.ts
@@ -0,0 +1,4 @@
+import { Controller } from '@nestjs/common';
+
+@Controller('chat')
+export class ChatController {}
diff --git a/backend/src/chat/chat.gateway.spec.ts b/backend/src/chat/chat.gateway.spec.ts
new file mode 100644
index 000000000..96743462b
--- /dev/null
+++ b/backend/src/chat/chat.gateway.spec.ts
@@ -0,0 +1,234 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { io, Socket } from 'socket.io-client';
+import { ChatRoom, User } from '@prisma/client';
+import { IoAdapter } from '@nestjs/platform-socket.io';
+import { INestApplication } from '@nestjs/common';
+
+import { TestModule } from '../test/test.module';
+import { PrismaService } from '../prisma/prisma.service';
+
+import { CreateChannelDto, JoinChannelDto } from './dto/Channel.dto';
+import { ChatGateway } from './chat.gateway';
+import { MessageDto } from './dto/message.dto';
+
+type testUser = {
+  user: User;
+  socket: Socket;
+};
+
+const modelNames = ['chatRoom', 'user'];
+const USERNUM = 10;
+
+const createTestUsers = async (prismaService: PrismaService) => {
+  const testUsers: testUser[] = [];
+  for (let i = 0; i < USERNUM; i++) {
+    const sock: Socket = io('http://localhost:8001');
+
+    const user: User = await prismaService.user.upsert({
+      where: {
+        email: `chatTestUser${i}@test.com`,
+      },
+      update: {},
+      create: {
+        email: `chatTestUser${i}@test.com`,
+        username: `chatTestUser${i}`,
+        hashedPassword: `chatTestUser${i}`,
+      },
+    });
+
+    testUsers.push({ user, socket: sock });
+  }
+  return testUsers;
+};
+
+const cleanupDatabase = async (
+  modelNames: string[],
+  prisma: PrismaService,
+): Promise<void> => {
+  console.log(modelNames);
+  // prisma.user prisma.chatroom 的なのになる
+  for (const name of modelNames) {
+    await (prisma as any)[name].deleteMany({});
+  }
+};
+
+const emitAndWaitForEvent = async <T>(
+  eventName: string,
+  socket: Socket,
+  dto: T,
+) => {
+  return new Promise((resolve) => {
+    socket.on(eventName, async () => resolve(null));
+    socket.emit(eventName, dto);
+  });
+};
+
+describe('ChatGateway', () => {
+  let gateway: ChatGateway;
+  let prismaService: PrismaService;
+  let testUsers: testUser[];
+  let room: ChatRoom | null;
+  let app: INestApplication;
+
+  beforeAll(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      imports: [TestModule],
+      providers: [ChatGateway, PrismaService],
+    }).compile();
+
+    gateway = module.get<ChatGateway>(ChatGateway);
+    prismaService = module.get<PrismaService>(PrismaService);
+
+    app = module.createNestApplication();
+    app.useWebSocketAdapter(new IoAdapter(app));
+    await app.listen(8001);
+
+    testUsers = [];
+    testUsers = await createTestUsers(prismaService);
+
+    testUsers.map((testUser) => {
+      testUser.socket.on('connect', () => {
+        console.log(`connected ${testUser.user.username}`);
+      });
+    });
+  });
+  afterAll(async () => {
+    testUsers.map((testUser) => {
+      testUser.socket.off('connect', () => {
+        console.log(`dissconnected ${testUser.user.username}`);
+      });
+    });
+
+    testUsers.map((testUser) => {
+      testUser.socket.disconnect();
+    });
+
+    await app.close();
+    await cleanupDatabase(modelNames, prismaService);
+  });
+
+  test('should be defined', () => {
+    expect(gateway).toBeDefined();
+  });
+
+  describe('create Channel', () => {
+    test('users[0]が部屋を作成', async () => {
+      const user: testUser = testUsers[0];
+      const createChannelDto: CreateChannelDto = {
+        roomName: 'testroom',
+        userId: user.user.id,
+      };
+      await emitAndWaitForEvent<CreateChannelDto>(
+        'createChannel',
+        user.socket,
+        createChannelDto,
+      );
+
+      room = await prismaService.chatRoom.findFirst({
+        where: {
+          roomName: 'testroom',
+        },
+      });
+
+      expect(room?.roomName).toEqual(createChannelDto.roomName);
+    });
+  });
+
+  describe('join Channel', () => {
+    let roomId: string;
+    beforeEach(() => {
+      if (!room) {
+        throw Error('room is not created');
+      }
+      roomId = room.id;
+    });
+
+    test('users[1]~users[9]が部屋に参加', async () => {
+      const promises: Promise<unknown>[] = [];
+
+      testUsers.slice(1).map((testUser) => {
+        const joinChannel: JoinChannelDto = {
+          userId: testUser.user.id,
+          chatRoomId: roomId,
+        };
+        const joinPromise = emitAndWaitForEvent<JoinChannelDto>(
+          'joinChannel',
+          testUser.socket,
+          joinChannel,
+        );
+        promises.push(joinPromise);
+      });
+
+      await Promise.all(promises).then(async () => {
+        const MemberList = await prismaService.roomMember.findMany({
+          where: {
+            chatRoomId: roomId,
+          },
+        });
+        expect(MemberList.length).toEqual(USERNUM);
+      });
+    });
+  });
+
+  describe('sendMessage', () => {
+    let roomId: string;
+    beforeEach(() => {
+      if (!room) {
+        throw Error('room is not created');
+      }
+      roomId = room.id;
+    });
+
+    test('users[0]が送信したメッセージがDBに保存されるか', async () => {
+      const user: testUser = testUsers[0];
+      const messageDto: MessageDto = {
+        content: 'test message',
+        userId: user.user.id,
+        chatRoomId: roomId,
+      };
+
+      await emitAndWaitForEvent<MessageDto>(
+        'sendMessage',
+        user.socket,
+        messageDto,
+      );
+      const dbMsg = await prismaService.message.findFirst({
+        where: {
+          chatRoomId: roomId,
+        },
+      });
+
+      expect(dbMsg?.content).toEqual(messageDto.content);
+    });
+
+    test('users[0]が送信したメッセージが全員に送信されるか', async () => {
+      const user = testUsers[0];
+      const messageDto: MessageDto = {
+        content: 'test message',
+        userId: user.user.id,
+        chatRoomId: roomId,
+      };
+      const promises: Promise<unknown>[] = [];
+
+      let receivedCount = 0;
+
+      testUsers.map((user) => {
+        const joinPromise = new Promise((resolve) => {
+          user.socket.on('sendMessage', async () => {
+            receivedCount++;
+            console.log(receivedCount);
+            resolve(null);
+          });
+        });
+
+        promises.push(joinPromise);
+      });
+
+      user.socket.emit('sendMessage', messageDto);
+
+      Promise.all(promises).then(() => {
+        expect(receivedCount).toEqual(USERNUM);
+      });
+    });
+  });
+});
diff --git a/backend/src/chat/chat.gateway.ts b/backend/src/chat/chat.gateway.ts
new file mode 100644
index 000000000..c04eff1aa
--- /dev/null
+++ b/backend/src/chat/chat.gateway.ts
@@ -0,0 +1,78 @@
+import {
+  SubscribeMessage,
+  WebSocketGateway,
+  WebSocketServer,
+} from '@nestjs/websockets';
+import { Socket, Server } from 'socket.io';
+
+import { PrismaService } from '../prisma/prisma.service';
+
+import { MessageDto } from './dto/message.dto';
+import { CreateChannelDto, JoinChannelDto } from './dto/Channel.dto';
+@WebSocketGateway({
+  cors: {
+    origin: '*',
+  },
+})
+export class ChatGateway {
+  @WebSocketServer()
+  server: Server;
+  constructor(private prisma: PrismaService) {}
+  handleConnection(client: Socket) {
+    // TODO jwtができたら接続時にdbに保存されてる所属しているチャンネルに全てにclient.joinする
+    console.log('chat Connection');
+    console.log(client.id);
+  }
+
+  handleDisconnect(client: Socket) {
+    console.log('chat Disconnection');
+    console.log(client.id);
+  }
+  @SubscribeMessage('createChannel')
+  async createChannel(client: Socket, createChannelDto: CreateChannelDto) {
+    const createdRoom = await this.prisma.chatRoom.create({
+      data: {
+        roomName: createChannelDto.roomName,
+      },
+    });
+    await this.prisma.roomMember.create({
+      data: {
+        userId: createChannelDto.userId,
+        chatRoomId: createdRoom.id,
+      },
+    });
+    client.join(createdRoom.id.toString());
+    this.server.emit('createChannel', createdRoom);
+  }
+
+  @SubscribeMessage('joinChannel')
+  async joinChannel(client: Socket, joinChannelDto: JoinChannelDto) {
+    const addedUser = await this.prisma.roomMember.create({
+      data: {
+        userId: joinChannelDto.userId,
+        chatRoomId: joinChannelDto.chatRoomId,
+      },
+    });
+    client.join(addedUser.chatRoomId.toString());
+    this.server
+      .to(addedUser.chatRoomId.toString())
+      .emit('joinChannel', addedUser);
+  }
+
+  @SubscribeMessage('sendMessage')
+  async sendMessage(client: Socket, messageDto: MessageDto) {
+    const msg = await this.prisma.message.create({
+      data: {
+        content: messageDto.content,
+        userId: messageDto.userId,
+        chatRoomId: messageDto.chatRoomId,
+      },
+    });
+    const roomMsgs = await this.prisma.message.findMany({
+      where: {
+        chatRoomId: messageDto.chatRoomId,
+      },
+    });
+    this.server.to(msg.chatRoomId.toString()).emit('sendMessage', roomMsgs);
+  }
+}
diff --git a/backend/src/chat/chat.module.ts b/backend/src/chat/chat.module.ts
new file mode 100644
index 000000000..59398df5c
--- /dev/null
+++ b/backend/src/chat/chat.module.ts
@@ -0,0 +1,14 @@
+import { Module } from '@nestjs/common';
+
+import { PrismaModule } from '../prisma/prisma.module';
+
+import { ChatService } from './chat.service';
+import { ChatGateway } from './chat.gateway';
+import { ChatController } from './chat.controller';
+
+@Module({
+  imports: [PrismaModule],
+  providers: [ChatService, ChatGateway],
+  controllers: [ChatController],
+})
+export class ChatModule {}
diff --git a/backend/src/chat/chat.service.spec.ts b/backend/src/chat/chat.service.spec.ts
new file mode 100644
index 000000000..60e28ba74
--- /dev/null
+++ b/backend/src/chat/chat.service.spec.ts
@@ -0,0 +1,19 @@
+import { Test, TestingModule } from '@nestjs/testing';
+
+import { ChatService } from './chat.service';
+
+describe('ChatService', () => {
+  let service: ChatService;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [ChatService],
+    }).compile();
+
+    service = module.get<ChatService>(ChatService);
+  });
+
+  test('should be defined', () => {
+    expect(service).toBeDefined();
+  });
+});
diff --git a/backend/src/chat/chat.service.ts b/backend/src/chat/chat.service.ts
new file mode 100644
index 000000000..408edccb1
--- /dev/null
+++ b/backend/src/chat/chat.service.ts
@@ -0,0 +1,4 @@
+import { Injectable } from '@nestjs/common';
+
+@Injectable()
+export class ChatService {}
diff --git a/backend/src/chat/dto/Channel.dto.ts b/backend/src/chat/dto/Channel.dto.ts
new file mode 100644
index 000000000..54c089588
--- /dev/null
+++ b/backend/src/chat/dto/Channel.dto.ts
@@ -0,0 +1,8 @@
+export class JoinChannelDto {
+  chatRoomId: string;
+  userId: string;
+}
+export class CreateChannelDto {
+  roomName: string;
+  userId: string;
+}
diff --git a/backend/src/chat/dto/message.dto.ts b/backend/src/chat/dto/message.dto.ts
new file mode 100644
index 000000000..3e4b884b2
--- /dev/null
+++ b/backend/src/chat/dto/message.dto.ts
@@ -0,0 +1,5 @@
+export class MessageDto {
+  content: string;
+  userId: string;
+  chatRoomId: string;
+}