diff --git a/src/_actions/ChatAction.ts b/src/_actions/ChatAction.ts
new file mode 100644
index 0000000..a18cb27
--- /dev/null
+++ b/src/_actions/ChatAction.ts
@@ -0,0 +1,22 @@
+import { NEW_CHAT_ROOM, LEAVE_CHAT_ROOM, RECEIVE_MESSAGE, SEND_MESSAGE } from "./types";
+import { TargetChatRoom, TargetMessage } from "./ChatActionTypes";
+
+export const createChatRoom = (targetChatRoom: TargetChatRoom) => ({
+  type: NEW_CHAT_ROOM,
+  payload: targetChatRoom,
+});
+
+export const leaveChatRoom = (targetChatRoom: TargetChatRoom) => ({
+  type: LEAVE_CHAT_ROOM,
+  payload: targetChatRoom,
+});
+
+export const sendMessage = (targetMessage: TargetMessage) => ({
+  type: SEND_MESSAGE,
+  payload: targetMessage,
+});
+
+export const receiveMessage = (targetMessage: TargetMessage) => ({
+  type: RECEIVE_MESSAGE,
+  payload: targetMessage,
+});
\ No newline at end of file
diff --git a/src/_actions/ChatActionTypes.ts b/src/_actions/ChatActionTypes.ts
new file mode 100644
index 0000000..c93cc86
--- /dev/null
+++ b/src/_actions/ChatActionTypes.ts
@@ -0,0 +1,9 @@
+export interface TargetChatRoom {
+  id: number
+  title: String,
+  messages: Array<String>
+}
+
+export interface TargetMessage {
+  content: String
+}
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diff --git a/src/_actions/types.ts b/src/_actions/types.ts
new file mode 100644
index 0000000..a8e29bd
--- /dev/null
+++ b/src/_actions/types.ts
@@ -0,0 +1,4 @@
+export const NEW_CHAT_ROOM = "new_chat_room" as const;
+export const LEAVE_CHAT_ROOM = "leave_chat_room" as const;
+export const SEND_MESSAGE = "send_message" as const;
+export const RECEIVE_MESSAGE = "receive_message" as const;
diff --git a/src/_reducers/ChatReducer.ts b/src/_reducers/ChatReducer.ts
new file mode 100644
index 0000000..c6f6094
--- /dev/null
+++ b/src/_reducers/ChatReducer.ts
@@ -0,0 +1,41 @@
+import {
+  NEW_CHAT_ROOM,
+  LEAVE_CHAT_ROOM,
+  SEND_MESSAGE,
+  RECEIVE_MESSAGE
+} from '_actions/types';
+
+import {
+  createChatRoom,
+  leaveChatRoom,
+  sendMessage,
+  receiveMessage
+} from '_actions/ChatAction'
+
+type ChatAction = 
+  | ReturnType<typeof createChatRoom>
+  | ReturnType<typeof leaveChatRoom>
+  | ReturnType<typeof sendMessage>
+  | ReturnType<typeof receiveMessage>;
+
+type ChatState = {
+  chat: Array<Array<String>>;
+}
+
+const initialState: ChatState = {
+  chat : []
+}
+
+export default function chatReducer(
+  state: ChatState = initialState,
+  action: ChatAction
+  ) : ChatState {
+    switch(action.type) {
+      case NEW_CHAT_ROOM:
+        state.chat[action.payload.id] = [...action.payload.messages];
+        return {...state};
+      default:
+        return state;
+    }
+    
+}
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