diff --git a/src/app.tsx b/src/app.tsx
index b726880..1b41cb8 100644
--- a/src/app.tsx
+++ b/src/app.tsx
@@ -15,6 +15,7 @@ export interface ChatStore {
   apiKey: string;
   apiEndpoint: string;
   streamMode: boolean;
+  model: string;
 }
 
 const _defaultAPIEndpoint = "https://api.openai.com/v1/chat/completions";
@@ -22,7 +23,8 @@ const newChatStore = (
   apiKey = "",
   systemMessageContent = "你是一个有用的人工智能助理，根据我的提问和要求回答我的问题",
   apiEndpoint = _defaultAPIEndpoint,
-  streamMode = true
+  streamMode = true,
+  model = "gpt-3.5-turbo"
 ): ChatStore => {
   return {
     systemMessageContent: getDefaultParams("sys", systemMessageContent),
@@ -34,6 +36,7 @@ const newChatStore = (
     apiKey: getDefaultParams("key", apiKey),
     apiEndpoint: getDefaultParams("api", apiEndpoint),
     streamMode: getDefaultParams("mode", streamMode),
+    model: getDefaultParams("model", model),
   };
 };
 
@@ -71,7 +74,10 @@ export function App() {
     const key = `${STORAGE_NAME}-${index}`;
     const val = localStorage.getItem(key);
     if (val === null) return newChatStore();
-    return JSON.parse(val) as ChatStore;
+    const ret = JSON.parse(val) as ChatStore;
+    // handle read from old version chatstore
+    if (ret.model === undefined) ret.model = "gpt-3.5-turbo";
+    return ret;
   };
 
   const [chatStore, _setChatStore] = useState(
diff --git a/src/chatbox.tsx b/src/chatbox.tsx
index 29a44b2..1f1183d 100644
--- a/src/chatbox.tsx
+++ b/src/chatbox.tsx
@@ -102,6 +102,7 @@ export default function ChatBOX(props: {
     client.apiEndpoint = chatStore.apiEndpoint;
     client.sysMessageContent = chatStore.systemMessageContent;
     client.messages = chatStore.history.slice(chatStore.postBeginIndex);
+    client.model = chatStore.model;
     // try forget message before sending request
     client.forgetSomeMessages();
     try {
@@ -198,6 +199,8 @@ export default function ChatBOX(props: {
           <p className="break-all opacity-60 p-6 rounded bg-white my-3 text-left dark:text-black">
             暂无历史对话记录
             <br />
+            ⚙Model: {chatStore.model}
+            <br />
             ⚙Key: {chatStore.apiKey}
             <br />
             ⚙Endpoint: {chatStore.apiEndpoint}
diff --git a/src/chatgpt.ts b/src/chatgpt.ts
index 02c918e..73cc5e5 100644
--- a/src/chatgpt.ts
+++ b/src/chatgpt.ts
@@ -42,6 +42,7 @@ class Chat {
   max_tokens: number;
   tokens_margin: number;
   apiEndpoint: string;
+  model: string;
 
   constructor(
     OPENAI_API_KEY: string | undefined,
@@ -50,6 +51,7 @@ class Chat {
       max_tokens = 4096,
       tokens_margin = 1024,
       apiEndPoint = "https://api.openai.com/v1/chat/completions",
+      model = "gpt-3.5-turbo",
     } = {}
   ) {
     if (OPENAI_API_KEY === undefined) {
@@ -62,6 +64,7 @@ class Chat {
     this.tokens_margin = tokens_margin;
     this.sysMessageContent = systemMessage;
     this.apiEndpoint = apiEndPoint;
+    this.model = model;
   }
 
   _fetch(stream = false) {
@@ -72,7 +75,7 @@ class Chat {
         "Content-Type": "application/json",
       },
       body: JSON.stringify({
-        model: "gpt-3.5-turbo",
+        model: this.model,
         messages: [
           { role: "system", content: this.sysMessageContent },
           ...this.messages,
diff --git a/src/settings.tsx b/src/settings.tsx
index df516b0..f5c0263 100644
--- a/src/settings.tsx
+++ b/src/settings.tsx
@@ -17,6 +17,41 @@ const Help = (props: { children: any; help: string }) => {
   );
 };
 
+const SelectModel = (props: {
+  chatStore: ChatStore;
+  setChatStore: (cs: ChatStore) => void;
+  help: string;
+}) => {
+  // model and their max token
+  const options: Record<string, number> = {
+    "gpt-3.5-turbo": 4096,
+    "gpt-3.5-turbo-0301": 4096,
+    "gpt-4": 8192,
+    "gpt-4-0314": 8192,
+    "gpt-4-32k": 32768,
+    "gpt-4-32k-0314": 32768,
+  };
+  return (
+    <Help help={props.help}>
+      <label className="m-2 p-2">Model</label>
+      <select
+        className="m-2 p-2"
+        value={props.chatStore.model}
+        onChange={(event: any) => {
+          const model = event.target.value as string;
+          props.chatStore.model = model;
+          props.chatStore.maxTokens = options[model];
+          props.setChatStore({ ...props.chatStore });
+        }}
+      >
+        {Object.keys(options).map((opt) => (
+          <option value={opt}>{opt}</option>
+        ))}
+      </select>
+    </Help>
+  );
+};
+
 const Input = (props: {
   chatStore: ChatStore;
   setChatStore: (cs: ChatStore) => void;
@@ -101,7 +136,9 @@ export default (props: {
       props.chatStore.apiKey
     )}&api=${encodeURIComponent(props.chatStore.apiEndpoint)}&mode=${
       props.chatStore.streamMode ? "stream" : "fetch"
-    }&sys=${encodeURIComponent(props.chatStore.systemMessageContent)}`;
+    }&model=${props.chatStore.model}&sys=${encodeURIComponent(
+      props.chatStore.systemMessageContent
+    )}`;
   return (
     <div className="left-0 top-0 overflow-scroll flex justify-center absolute w-screen h-full bg-black bg-opacity-50 z-10">
       <div className="m-2 p-2 bg-white rounded-lg h-fit">
@@ -128,9 +165,13 @@ export default (props: {
             help="流模式，使用 stream mode 将可以动态看到生成内容，但无法准确计算 token 数量，在 token 数量过多时可能会裁切过多或过少历史消息"
             {...props}
           />
+          <SelectModel
+            help="模型，默认 3.5。不同模型性能和定价也不同，请参考 API 文档。"
+            {...props}
+          />
           <Number
             field="maxTokens"
-            help="最大 token 数量，这个详情参考 OPENAI API 文档"
+            help="最大 token 数量。如果使用非gpt-3.5模型，请手动修改上限。gpt-4 & gpt-4-0314: 8192。gpt-4-32k & gpt-4-32k-0314: 32768"
             readOnly={false}
             {...props}
           />