diff --git a/backend/chatServer/src/chat/chat.error.ts b/backend/chatServer/src/chat/chat.error.ts
new file mode 100644
index 00000000..691b7ab2
--- /dev/null
+++ b/backend/chatServer/src/chat/chat.error.ts
@@ -0,0 +1,54 @@
+import { HttpStatus } from '@nestjs/common';
+import { WsException } from '@nestjs/websockets';
+
+class ChatException extends WsException {
+  statusCode: number;
+  constructor({ statusCode, message } : ChatError , public roomId?: string) {
+    super({ statusCode, message, roomId });
+    this.statusCode = statusCode;
+  }
+
+  getError(): object {
+    return {
+      statusCode: this.statusCode,
+      msg: this.message,
+      roomId: this.roomId || null,
+    };
+  }
+}
+
+interface ChatError {
+  statusCode: number;
+  message: string;
+}
+
+const CHATTING_SOCKET_ERROR = {
+  ROOM_EMPTY: {
+    statusCode: HttpStatus.BAD_REQUEST,
+    message: '유저가 참여하고 있는 채팅방이 없습니다.'
+  },
+
+  ROOM_EXISTED: {
+    statusCode: HttpStatus.BAD_REQUEST,
+    message: '이미 존재하는 방입니다.'
+  },
+
+  INVALID_USER: {
+    statusCode: HttpStatus.UNAUTHORIZED,
+    message: '유효하지 않는 유저입니다.'
+  },
+
+  QUESTION_EMPTY: {
+    statusCode: HttpStatus.BAD_REQUEST,
+    message: '유효하지 않은 질문입니다.'
+  },
+
+  BAN_USER: {
+    statusCode: HttpStatus.FORBIDDEN,
+    message: '호스트에 의해 밴 당한 유저입니다.'
+  }
+
+
+};
+export { CHATTING_SOCKET_ERROR, ChatException };
+
diff --git a/backend/chatServer/src/chat/chat.gateway.ts b/backend/chatServer/src/chat/chat.gateway.ts
index 7966bd42..de7ad5b1 100644
--- a/backend/chatServer/src/chat/chat.gateway.ts
+++ b/backend/chatServer/src/chat/chat.gateway.ts
@@ -6,21 +6,21 @@ import {
   OnGatewayConnection,
   OnGatewayDisconnect,
   MessageBody,
-  ConnectedSocket,
+  ConnectedSocket
 } from '@nestjs/websockets';
 import { UseGuards } from '@nestjs/common';
 import { Server, Socket } from 'socket.io';
 import {
-  CHATTING_SOCKET_DEFAULT_EVENT,
-  CHATTING_SOCKET_RECEIVE_EVENT, CHATTING_SOCKET_SEND_EVENT
+  CHATTING_SOCKET_DEFAULT_EVENT, CHATTING_SOCKET_RECEIVE_EVENT, CHATTING_SOCKET_SEND_EVENT
 } from '../event/constants';
 import {
+  BanUserIncomingMessageDto,
   NormalIncomingMessageDto, NoticeIncomingMessageDto, QuestionDoneIncomingMessageDto, QuestionIncomingMessageDto
 } from '../event/dto/IncomingMessage.dto';
 import { JoiningRoomDto } from '../event/dto/JoiningRoom.dto';
 import { RoomService } from '../room/room.service';
 import { createAdapter } from '@socket.io/redis-adapter';
-import { HostGuard, MessageGuard } from './chat.guard';
+import { BlacklistGuard, HostGuard, MessageGuard } from './chat.guard';
 import { LeavingRoomDto } from '../event/dto/LeavingRoom.dto';
 import {
   NormalOutgoingMessageDto,
@@ -28,6 +28,7 @@ import {
   QuestionOutgoingMessageDto
 } from '../event/dto/OutgoingMessage.dto';
 import { QuestionDto } from '../event/dto/Question.dto';
+import { ChatException, CHATTING_SOCKET_ERROR } from './chat.error';
 
 @WebSocketGateway({ cors: true })
 export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewayDisconnect {
@@ -69,6 +70,7 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
   }
 
   // 특정 방에 참여하기 위한 메서드
+  @UseGuards(BlacklistGuard)
   @SubscribeMessage(CHATTING_SOCKET_DEFAULT_EVENT.JOIN_ROOM)
   async handleJoinRoom(client: Socket, payload: JoiningRoomDto) {
     const { roomId, userId } = payload;
@@ -93,7 +95,7 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
   }
 
   // 방에 NORMAL 메시지를 보내기 위한 메서드
-  @UseGuards(MessageGuard)
+  @UseGuards(MessageGuard, BlacklistGuard)
   @SubscribeMessage(CHATTING_SOCKET_SEND_EVENT.NORMAL)
   async handleNormalMessage(@ConnectedSocket() client: Socket, @MessageBody() payload: NormalIncomingMessageDto) {
     const { roomId, userId, msg } = payload;
@@ -103,7 +105,8 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
       ...user,
       msg,
       msgTime: new Date().toISOString(),
-      msgType: 'normal'
+      msgType: 'normal',
+      socketId: client.id
     };
     console.log('Normal Message Come In: ', normalOutgoingMessage);
     const hostId = await this.roomService.getHostOfRoom(roomId);
@@ -121,7 +124,7 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
   }
 
   // 방에 QUESTION 메시지를 보내기 위한 메서드
-  @UseGuards(MessageGuard)
+  @UseGuards(MessageGuard,BlacklistGuard)
   @SubscribeMessage(CHATTING_SOCKET_SEND_EVENT.QUESTION)
   async handleQuestionMessage(@ConnectedSocket() client: Socket, @MessageBody() payload: QuestionIncomingMessageDto) {
     const { roomId, msg } = payload;
@@ -132,7 +135,8 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
       msg,
       msgTime: new Date().toISOString(),
       msgType: 'question',
-      questionDone: false
+      questionDone: false,
+      socketId: client.id
     };
 
     const question: QuestionOutgoingMessageDto = await this.roomService.addQuestion(roomId, questionWithoutId);
@@ -150,8 +154,7 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
   }
 
   // 방에 NOTICE 메시지를 보내기 위한 메서드
-  @UseGuards(MessageGuard)
-  @UseGuards(HostGuard)
+  @UseGuards(MessageGuard, HostGuard)
   @SubscribeMessage(CHATTING_SOCKET_SEND_EVENT.NOTICE)
   async handleNoticeMessage(@ConnectedSocket() client: Socket, @MessageBody() payload: NoticeIncomingMessageDto) {
     const { roomId, msg } = payload;
@@ -165,4 +168,20 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
     };
     this.server.to(roomId).emit(CHATTING_SOCKET_RECEIVE_EVENT.NOTICE, noticeOutgoingMessage);
   }
+
+  @UseGuards(HostGuard)
+  @SubscribeMessage(CHATTING_SOCKET_DEFAULT_EVENT.BAN_USER)
+  async handleBanUserMessage(@ConnectedSocket() client: Socket, @MessageBody() payload: BanUserIncomingMessageDto) {
+    const { roomId, socketId } = payload;
+    const banUser = this.server.sockets.sockets.get(socketId);
+    const address = banUser?.handshake.address.replaceAll('::ffff:', '');
+
+    if(!address) throw new ChatException(CHATTING_SOCKET_ERROR.INVALID_USER);
+
+    const forwarded = banUser?.handshake.headers.forwarded ?? address;
+    console.log('ban:', roomId, address, forwarded);
+
+    await this.roomService.addUserToBlacklist(roomId, address, forwarded);
+    console.log(await this.roomService.getUserBlacklist(roomId, address));
+  }
 }
diff --git a/backend/chatServer/src/chat/chat.guard.ts b/backend/chatServer/src/chat/chat.guard.ts
index 270defc3..021baac0 100644
--- a/backend/chatServer/src/chat/chat.guard.ts
+++ b/backend/chatServer/src/chat/chat.guard.ts
@@ -1,5 +1,8 @@
 import { Injectable, CanActivate, ExecutionContext } from '@nestjs/common';
 import { RoomService } from '../room/room.service';
+import { Socket } from 'socket.io';
+
+import { ChatException, CHATTING_SOCKET_ERROR } from './chat.error';
 
 @Injectable()
 export class MessageGuard implements CanActivate {
@@ -22,3 +25,30 @@ export class HostGuard implements CanActivate {
     return hostId === userId;
   }
 }
+
+@Injectable()
+export class BlacklistGuard implements CanActivate {
+  constructor(private roomService: RoomService) {};
+  async canActivate(context: ExecutionContext) {
+    const payload = context.switchToWs().getData();
+    const { roomId } = payload;
+
+    const client: Socket = context.switchToWs().getClient<Socket>();
+    const address = client.handshake.address.replaceAll('::ffff:', '');
+    const forwarded = client.handshake.headers.forwarded?.split(',')[0] ?? address;
+
+    const isValidUser = await this.whenJoinRoom(roomId, address, forwarded);
+
+    if(!isValidUser) throw new ChatException(CHATTING_SOCKET_ERROR.BAN_USER, roomId);
+    return true;
+  }
+
+  async whenJoinRoom(roomId: string, address: string, forwarded: string) {
+    console.log(roomId, address, forwarded);
+    const blacklistInRoom = await this.roomService.getUserBlacklist(roomId, address);
+    console.log(blacklistInRoom);
+    const isInBlacklistUser = blacklistInRoom.some((blackForwarded) => blackForwarded === forwarded);
+    console.log('blacklistInRoom:', isInBlacklistUser);
+    return !isInBlacklistUser;
+  }
+}
diff --git a/backend/chatServer/src/chat/chat.module.ts b/backend/chatServer/src/chat/chat.module.ts
index 51629715..bd285e1f 100644
--- a/backend/chatServer/src/chat/chat.module.ts
+++ b/backend/chatServer/src/chat/chat.module.ts
@@ -1,10 +1,10 @@
 import { Module } from '@nestjs/common';
 import { ChatGateway } from './chat.gateway';
 import { RoomModule } from '../room/room.module';
-import { MessageGuard } from './chat.guard';
+import { BlacklistGuard, HostGuard, MessageGuard } from './chat.guard';
 
 @Module({
   imports: [RoomModule],
-  providers: [ChatGateway, MessageGuard],
+  providers: [ChatGateway, MessageGuard, BlacklistGuard, HostGuard],
 })
 export class ChatModule {}
diff --git a/backend/chatServer/src/event/constants.ts b/backend/chatServer/src/event/constants.ts
index 2ce8d053..ce8fd0c6 100644
--- a/backend/chatServer/src/event/constants.ts
+++ b/backend/chatServer/src/event/constants.ts
@@ -1,8 +1,7 @@
-import { HttpStatus } from '@nestjs/common';
-
 const CHATTING_SOCKET_DEFAULT_EVENT = {
   JOIN_ROOM: 'join_room',
   LEAVE_ROOM: 'leave_room',
+  BAN_USER: 'ban_user',
 };
 
 const CHATTING_SOCKET_RECEIVE_EVENT = {
@@ -20,28 +19,4 @@ const CHATTING_SOCKET_SEND_EVENT = {
   NOTICE: 'send_notice'
 };
 
-const CHATTING_SOCKET_ERROR = {
-  ROOM_EMPTY : {
-    statusCode: HttpStatus.BAD_REQUEST,
-    message: '유저가 참여하고 있는 채팅방이 없습니다.'
-  },
-
-  ROOM_EXISTED: {
-    statusCode: HttpStatus.BAD_REQUEST,
-    message: '이미 존재하는 방입니다.'
-  },
-
-  INVALID_USER: {
-    statusCode: HttpStatus.UNAUTHORIZED,
-    message: '유효하지 않는 유저입니다.'
-  },
-
-  QUESTION_EMPTY: {
-    statusCode: HttpStatus.BAD_REQUEST,
-    message: '유효하지 않은 질문입니다.'
-  },
-
-
-};
-
-export { CHATTING_SOCKET_DEFAULT_EVENT, CHATTING_SOCKET_SEND_EVENT, CHATTING_SOCKET_RECEIVE_EVENT, CHATTING_SOCKET_ERROR};
+export { CHATTING_SOCKET_DEFAULT_EVENT, CHATTING_SOCKET_SEND_EVENT, CHATTING_SOCKET_RECEIVE_EVENT};
diff --git a/backend/chatServer/src/event/dto/OutgoingMessage.dto.ts b/backend/chatServer/src/event/dto/OutgoingMessage.dto.ts
index 8557a5ed..f77eac50 100644
--- a/backend/chatServer/src/event/dto/OutgoingMessage.dto.ts
+++ b/backend/chatServer/src/event/dto/OutgoingMessage.dto.ts
@@ -5,6 +5,7 @@ class DefaultOutgoingMessageDto {
   roomId: string = '';
   nickname: string = '';
   color: string = '';
+  entryTime: string = '';
   msgTime: string = new Date().toISOString();
 }
 
diff --git a/backend/chatServer/src/event/dto/Question.dto.ts b/backend/chatServer/src/event/dto/Question.dto.ts
index 3a7c78bb..67ab8788 100644
--- a/backend/chatServer/src/event/dto/Question.dto.ts
+++ b/backend/chatServer/src/event/dto/Question.dto.ts
@@ -4,6 +4,7 @@ class QuestionDto {
   roomId: string = '';
   nickname: string = '';
   color: string = '';
+  entryTime: string = '';
   msg: string = '';
   msgTime: string = new Date().toISOString();
   msgType: OutgoingMessageType = 'question';
diff --git a/backend/chatServer/src/room/room.repository.ts b/backend/chatServer/src/room/room.repository.ts
index 6bb90b68..3289d2d0 100644
--- a/backend/chatServer/src/room/room.repository.ts
+++ b/backend/chatServer/src/room/room.repository.ts
@@ -1,8 +1,9 @@
 import { Injectable } from '@nestjs/common';
 import { Cluster } from 'ioredis';
-import { CHATTING_SOCKET_ERROR } from '../event/constants';
-import { WsException } from '@nestjs/websockets';
 import { QuestionDto } from '../event/dto/Question.dto';
+import { ChatException, CHATTING_SOCKET_ERROR } from '../chat/chat.error';
+
+type FORWARDED = string;
 
 @Injectable()
 export class RoomRepository {
@@ -10,6 +11,7 @@ export class RoomRepository {
   roomIdPrefix = 'room:';
   questionPrefix = 'question';
   questionIdPrefix = 'id';
+  blacklistPrefix = 'blacklist';
 
   injectClient(redisClient: Cluster){
     this.redisClient = redisClient;
@@ -27,6 +29,14 @@ export class RoomRepository {
     return `${this.getRoomStringWithPrefix(roomId)}-${this.questionPrefix}-${this.questionIdPrefix}`;
   }
 
+  private getUserBlacklistStringWithPrefix(address:string){
+    return `${this.blacklistPrefix}:${address}`;
+  }
+
+  private getUserBlacklistInRoomWithPrefix(roomId:string, address:string){
+    return `${this.getRoomStringWithPrefix(roomId)}-${this.getUserBlacklistStringWithPrefix(address)}`;
+  }
+
   private async lindex<T>(key: string, index: number){
     const result = await this.redisClient.lindex(key, index);
     if(result) return JSON.parse(result) as T;
@@ -35,12 +45,12 @@ export class RoomRepository {
 
   private async lrange<T>(key: string, start: number, end: number){
     const result = await this.redisClient.lrange(key, start, end);
-    return result.map((r) => JSON.parse(r)) as T;
+    return result as T;
   }
 
   private async getData<T>(key: string) {
     const result = await this.redisClient.get(key);
-    if(result) return JSON.parse(result) as T;
+    if(result) return typeof result === 'string' ? result as T : JSON.parse(result) as T;
     return undefined;
   }
 
@@ -50,7 +60,7 @@ export class RoomRepository {
 
   async getHost(roomId: string) {
     const hostId = await this.redisClient.get(this.getRoomStringWithPrefix(roomId));
-    if(!hostId) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if(!hostId) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
     return hostId;
   }
 
@@ -72,7 +82,7 @@ export class RoomRepository {
 
   async markQuestionAsDone(roomId: string, questionId: number): Promise<QuestionDto> {
     const question = await this.getQuestion(roomId, questionId);
-    if(!question) throw new WsException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
+    if(!question) throw new ChatException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
     question.questionDone = true;
     this.redisClient.lset(this.getQuestionStringWithPrefix(roomId), questionId, JSON.stringify(question));
     return question;
@@ -88,7 +98,7 @@ export class RoomRepository {
   async getQuestion(roomId: string, questionId: number): Promise<QuestionDto> {
     const question = await this.lindex<Omit<QuestionDto, 'questionId'>>(this.getQuestionStringWithPrefix(roomId), questionId);
     if(question) return {...question, questionId };
-    throw new WsException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
+    throw new ChatException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
   }
 
   async getQuestionId(roomId: string) {
@@ -102,4 +112,16 @@ export class RoomRepository {
   }
 
 
+  async getUserBlacklist(roomId: string, address: string): Promise<FORWARDED[]> {
+    const userBlacklist = await this.lrange<FORWARDED[]>(this.getUserBlacklistInRoomWithPrefix(roomId, address), 0, -1);
+    console.log('blacklist', userBlacklist);
+    if (!userBlacklist) return [];
+    return userBlacklist;
+  }
+
+  async addUserBlacklistToRoom(roomId: string, address: string, forwarded: string){
+    console.log(roomId, address, forwarded);
+    console.log(this.getUserBlacklistInRoomWithPrefix(roomId, address));
+    return this.redisClient.rpush(this.getUserBlacklistInRoomWithPrefix(roomId, address), forwarded);
+  }
 }
diff --git a/backend/chatServer/src/room/room.service.ts b/backend/chatServer/src/room/room.service.ts
index 3246d45e..e72126ec 100644
--- a/backend/chatServer/src/room/room.service.ts
+++ b/backend/chatServer/src/room/room.service.ts
@@ -1,8 +1,6 @@
 import { Injectable, OnModuleDestroy, OnModuleInit } from '@nestjs/common';
 import { Cluster, Redis } from 'ioredis';
 import { createAdapter } from '@socket.io/redis-adapter';
-import { WsException } from '@nestjs/websockets';
-import { CHATTING_SOCKET_ERROR } from '../event/constants';
 import { User } from './user.interface';
 import { getRandomAdjective, getRandomBrightColor, getRandomNoun } from '../utils/random';
 import { RoomRepository } from './room.repository';
@@ -12,6 +10,7 @@ import dotenv from 'dotenv';
 import path from 'path';
 import { fileURLToPath } from 'url';
 import { dirname } from 'path';
+import { ChatException, CHATTING_SOCKET_ERROR } from '../chat/chat.error';
 
 // 현재 파일의 URL을 파일 경로로 변환
 const __filename = fileURLToPath(import.meta.url);
@@ -28,7 +27,8 @@ function createRandomNickname(){
 function createRandomUserInstance(): User {
   return {
     nickname: createRandomNickname(),
-    color: getRandomBrightColor()
+    color: getRandomBrightColor(),
+    entryTime: new Date().toISOString()
   };
 }
 
@@ -85,13 +85,13 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
   // 방 삭제
   async deleteRoom(roomId: string) {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
     await this.redisRepository.deleteRoom(roomId);
   }
 
   async addQuestion(roomId: string, question: Omit<QuestionDto, 'questionId'>){
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
 
     return await this.redisRepository.addQuestionToRoom(roomId, question);
   }
@@ -102,7 +102,7 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
     question: Omit<QuestionDto, 'questionId'>,
   ): Promise<QuestionDto> {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
 
     return await this.redisRepository.addQuestionToRoom(roomId, question);
   }
@@ -110,24 +110,24 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
   // 특정 질문 완료 처리
   async markQuestionAsDone(roomId: string, questionId: number) {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
 
     const markedQuestion = await this.redisRepository.markQuestionAsDone(roomId, questionId);
-    if (!markedQuestion) throw new WsException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
+    if (!markedQuestion) throw new ChatException(CHATTING_SOCKET_ERROR.QUESTION_EMPTY);
     return markedQuestion;
   }
 
   // 방에 속한 모든 질문 조회
   async getQuestions(roomId: string): Promise<QuestionDto[]> {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
 
     return this.redisRepository.getQuestionsAll(roomId);
   }
 
   async getQuestionsNotDone(roomId: string): Promise<QuestionDto[]> {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
 
     return this.redisRepository.getQuestionsUnmarked(roomId);
   }
@@ -135,7 +135,7 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
   // 특정 질문 조회
   async getQuestion(roomId: string, questionId: number): Promise<QuestionDto> {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
     return this.redisRepository.getQuestion(roomId, questionId);
   }
 
@@ -149,7 +149,7 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
   // 유저 삭제
   async deleteUser(clientId: string) {
     const user = this.users.get(clientId);
-    if (!user) throw new WsException(CHATTING_SOCKET_ERROR.INVALID_USER);
+    if (!user) throw new ChatException(CHATTING_SOCKET_ERROR.INVALID_USER);
     this.users.delete(clientId);
     return user;
   }
@@ -157,13 +157,24 @@ export class RoomService implements OnModuleInit, OnModuleDestroy {
   // 특정 유저 조회
   async getUserByClientId(clientId: string) {
     const user = this.users.get(clientId);
-    if (!user) throw new WsException(CHATTING_SOCKET_ERROR.INVALID_USER);
+    if (!user) throw new ChatException(CHATTING_SOCKET_ERROR.INVALID_USER);
     return user;
   }
 
   async getHostOfRoom(roomId: string) {
     const roomExists = await this.redisRepository.isRoomExisted(roomId);
-    if (!roomExists) throw new WsException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
+    if (!roomExists) throw new ChatException(CHATTING_SOCKET_ERROR.ROOM_EMPTY);
     return await this.redisRepository.getHost(roomId);
   }
+
+  async getUserBlacklist(roomId: string, address: string) {
+    const roomExists = await this.redisRepository.isRoomExisted(roomId);
+    if (!roomExists) return [];
+
+    return await this.redisRepository.getUserBlacklist(roomId, address);
+  }
+
+  async addUserToBlacklist(roomId: string, address: string, forwarded: string){
+    return await this.redisRepository.addUserBlacklistToRoom(roomId, address, forwarded);
+  }
 }
diff --git a/backend/chatServer/src/room/user.interface.ts b/backend/chatServer/src/room/user.interface.ts
index a37d58a8..cba40228 100644
--- a/backend/chatServer/src/room/user.interface.ts
+++ b/backend/chatServer/src/room/user.interface.ts
@@ -1,4 +1,5 @@
 interface User {
+  entryTime: string;
   nickname: string;
   color: string;
 }