diff --git a/app/src/main/java/com/example/tampopo_client/models/Chatroom.java b/app/src/main/java/com/example/tampopo_client/models/Chatroom.java
index 74622ba..4fe8b21 100644
--- a/app/src/main/java/com/example/tampopo_client/models/Chatroom.java
+++ b/app/src/main/java/com/example/tampopo_client/models/Chatroom.java
@@ -1,49 +1,134 @@
 package com.example.tampopo_client.models;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class Chatroom {
-    private String chatroomId; // チャットルームのID
-    private String partnerUserId; // 相手ユーザーID
-    private String user1Id;    // 1人目のユーザーID
-    private String user2Id;    // 2人目のユーザーID
 
-    public Chatroom() {}
-    public Chatroom(String chatroomId, String user1Id, String user2Id) {
-        this.chatroomId = chatroomId;
+    private String chatRoomId;
+    private String user0Id;
+    private String user1Id;
+    private String newContent;
+    private String chatRoomNumber; // サーバーにも存在するので保持
+    private List<Message> messages = new ArrayList<>();
+    private List<String> users = new ArrayList<>();
+
+    // --- コンストラクタ ---
+    public Chatroom() {
+    }
+
+    public Chatroom(String chatRoomId, String user0Id, String user1Id) {
+        this.chatRoomId = chatRoomId;
+        this.user0Id = user0Id;
         this.user1Id = user1Id;
-        this.user2Id = user2Id;
+        this.users.add(user0Id);
+        this.users.add(user1Id);
     }
 
-
-    public Chatroom(String chatroomId,String partnerUserId) {
-        this.chatroomId = chatroomId;
-        this.partnerUserId = partnerUserId;
+    // --- Getter / Setter ---
+    public String getChatRoomId() {
+        return chatRoomId;
     }
 
-    public String getChatroomId() {
-        return chatroomId;
+    public void setChatRoomId(String chatRoomId) {
+        this.chatRoomId = chatRoomId;
     }
 
-    public void setChatroomId(String chatroomId) {
-        this.chatroomId = chatroomId;
+    public String getUser0Id() {
+        return user0Id;
+    }
+
+    public void setUser0Id(String user0Id) {
+        this.user0Id = user0Id;
     }
 
     public String getUser1Id() {
         return user1Id;
     }
 
-
-
-    public String getUser2Id() {
-        return user2Id;
+    public void setUser1Id(String user1Id) {
+        this.user1Id = user1Id;
     }
 
-
-    public String getPartnerUserId() {
-        return partnerUserId;
+    public String getNewContent() {
+        return newContent;
     }
 
-    public void setPartnerUserId(String partnerUserId) {
-        this.partnerUserId = partnerUserId;
+    public void setNewContent(String newContent) {
+        this.newContent = newContent;
     }
 
-}
+    public String getChatRoomNumber() {
+        return chatRoomNumber;
+    }
+
+    public void setChatRoomNumber(String chatRoomNumber) {
+        this.chatRoomNumber = chatRoomNumber;
+    }
+
+    public List<Message> getMessages() {
+        return messages;
+    }
+
+    public void setMessages(List<Message> messages) {
+        this.messages = messages;
+    }
+
+    public List<String> getUsers() {
+        return users;
+    }
+
+    public void setUsers(List<String> users) {
+        this.users = users;
+    }
+
+    // --- メッセージ追加 ---
+    public void addMessage(String senderId, String content) {
+        messages.add(new Message(senderId, content));
+    }
+
+    // --- ユーザー操作 ---
+    public void addUser(String userId) {
+        if (!users.contains(userId)) {
+            users.add(userId);
+        }
+    }
+
+    public boolean removeUser(String userId) {
+        return users.remove(userId);
+    }
+
+    public boolean isEmpty() {
+        return users.isEmpty();
+    }
+
+    // --- 内部クラス Message ---
+    public static class Message {
+        private String senderId;
+        private String content;
+
+        public Message() {
+        }
+
+        public Message(String senderId, String content) {
+            this.senderId = senderId;
+            this.content = content;
+        }
+
+        public String getSenderId() {
+            return senderId;
+        }
+
+        public void setSenderId(String senderId) {
+            this.senderId = senderId;
+        }
+
+        public String getContent() {
+            return content;
+        }
+
+        public void setContent(String content) {
+            this.content = content;
+        }
+    }
+}
\ No newline at end of file