diff --git a/app/[docs_id]/chatForm.tsx b/app/[docs_id]/chatForm.tsx
index a92afb0..f8939c2 100644
--- a/app/[docs_id]/chatForm.tsx
+++ b/app/[docs_id]/chatForm.tsx
@@ -1,25 +1,26 @@
 "use client";
 
 import { useState, FormEvent } from "react";
+import clsx from "clsx";
 import { askAI } from "@/app/actions/chatActions";
 import { StyledMarkdown } from "./markdown";
+import { useChatHistory, type Message } from "../hooks/useChathistory";
 import useSWR from "swr";
 import { getQuestionExample } from "../actions/questionExample";
 import { getLanguageName } from "../pagesList";
 
-export function ChatForm({
-  docs_id,
-  documentContent,
-}: {
-  docs_id: string;
+interface ChatFormProps {
   documentContent: string;
-}) {
+  sectionId: string;
+}
+
+export function ChatForm({ documentContent, sectionId }: ChatFormProps) {
+  const [messages, updateChatHistory] = useChatHistory(sectionId);
   const [inputValue, setInputValue] = useState("");
-  const [response, setResponse] = useState("");
   const [isLoading, setIsLoading] = useState(false);
   const [isFormVisible, setIsFormVisible] = useState(false);
 
-  const lang = getLanguageName(docs_id);
+  const lang = getLanguageName(sectionId);
   const { data: exampleData, error: exampleError } = useSWR(
     // 質問フォームを開いたときだけで良い
     isFormVisible ? { lang, documentContent } : null,
@@ -41,7 +42,9 @@ export function ChatForm({
   const handleSubmit = async (e: FormEvent<HTMLFormElement>) => {
     e.preventDefault();
     setIsLoading(true);
-    setResponse("");
+
+    const userMessage: Message = { sender: "user", text: inputValue };
+    updateChatHistory([userMessage]);
 
     let userQuestion = inputValue;
     if(!userQuestion && exampleData){
@@ -56,13 +59,21 @@ export function ChatForm({
     });
 
     if (result.error) {
-      setResponse(`エラー: ${result.error}`);
+      const errorMessage: Message = { sender: "ai", text: `エラー: ${result.error}`, isError: true };
+      updateChatHistory([userMessage, errorMessage]);
     } else {
-      setResponse(result.response);
+      const aiMessage: Message = { sender: "ai", text: result.response };
+      updateChatHistory([userMessage, aiMessage]);
+      setInputValue("");
     }
 
     setIsLoading(false);
   };
+
+  const handleClearHistory = () => {
+    updateChatHistory([]);
+  };
+  
   return (
     <>
       {isFormVisible && (
@@ -92,8 +103,8 @@ export function ChatForm({
               <button
                 className="btn btn-soft btn-secondary rounded-full"
                 onClick={() => setIsFormVisible(false)}
+                type="button"
               >
-
                 閉じる
               </button>
             </div>
@@ -122,14 +133,33 @@ export function ChatForm({
         </button>
       )}
 
-      {response && (
-        <article>
-          <h3 className="text-lg font-semibold mb-2">AIの回答</h3>
-          <div className="chat chat-start">
-            <div className="chat-bubble bg-secondary-content text-black" style={{maxWidth: "100%", wordBreak: "break-word"}}>
-              <div className="response-container"><StyledMarkdown content={response}/></div>
-            </div>
+      {messages.length > 0 && (
+        <article className="mt-4">
+          <div className="flex justify-between items-center mb-2">
+            <h3 className="text-lg font-semibold">AIとのチャット</h3>
+            <button
+              onClick={handleClearHistory}
+              className="btn btn-ghost btn-sm text-xs"
+              aria-label="チャット履歴を削除"
+            >
+              履歴を削除
+            </button>
           </div>
+          {messages.map((msg, index) => (
+            <div key={index} className={`chat ${msg.sender === 'user' ? 'chat-end' : 'chat-start'}`}>
+              <div 
+                className={clsx(
+                  "chat-bubble",
+                  { "bg-primary text-primary-content": msg.sender === 'user' },
+                  { "bg-secondary-content text-black": msg.sender === 'ai' && !msg.isError },
+                  { "chat-bubble-error": msg.isError }
+                )} 
+                style={{maxWidth: "100%", wordBreak: "break-word"}}
+              >
+                <StyledMarkdown content={msg.text} />
+              </div>
+            </div>
+          ))}
         </article>
       )}
 
@@ -141,4 +171,4 @@ export function ChatForm({
 
     </>
   );
-}
+}
\ No newline at end of file
diff --git a/app/[docs_id]/page.tsx b/app/[docs_id]/page.tsx
index 44b182d..0900973 100644
--- a/app/[docs_id]/page.tsx
+++ b/app/[docs_id]/page.tsx
@@ -45,11 +45,14 @@ export default async function Page({
 
   return (
     <div className="p-4">
-      {splitMdContent.map((section, index) => (
-        <div key={index} id={`${index}`}>
-          <Section key={index} docs_id={docs_id} section={section} />
-        </div>
-      ))}
+      {splitMdContent.map((section, index) => {
+        const sectionId = `${docs_id}-${index}`;
+        return (
+          <div key={index} id={`${index}`}>
+            <Section section={section} sectionId={sectionId} />
+          </div>
+        );
+      })}
     </div>
   );
 }
diff --git a/app/[docs_id]/section.tsx b/app/[docs_id]/section.tsx
index d705b44..9399c4a 100644
--- a/app/[docs_id]/section.tsx
+++ b/app/[docs_id]/section.tsx
@@ -24,14 +24,13 @@ interface ISectionCodeContext {
 const SectionCodeContext = createContext<ISectionCodeContext | null>(null);
 export const useSectionCode = () => useContext(SectionCodeContext);
 
-// 1つのセクションのタイトルと内容を表示する。内容はMarkdownとしてレンダリングする
-export function Section({
-  docs_id,
-  section,
-}: {
-  docs_id: string;
+interface SectionProps {
   section: MarkdownSection;
-}) {
+  sectionId: string;
+}
+
+// 1つのセクションのタイトルと内容を表示する。内容はMarkdownとしてレンダリングする
+export function Section({ section, sectionId }: SectionProps) {
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
   const [replOutputs, setReplOutputs] = useState<ReplCommand[]>([]);
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
@@ -77,7 +76,7 @@ export function Section({
       <div>
         <Heading level={section.level}>{section.title}</Heading>
         <StyledMarkdown content={section.content} />
-        <ChatForm docs_id={docs_id} documentContent={section.content} />
+         <ChatForm documentContent={section.content} sectionId={sectionId} />
       </div>
     </SectionCodeContext.Provider>
   );
diff --git a/app/hooks/useChathistory.ts b/app/hooks/useChathistory.ts
new file mode 100644
index 0000000..732fbd7
--- /dev/null
+++ b/app/hooks/useChathistory.ts
@@ -0,0 +1,40 @@
+"use client";
+
+import { useState, useEffect, useCallback } from 'react';
+
+export interface Message {
+  sender: "user" | "ai";
+  text: string;
+  isError?: boolean;
+}
+
+export const useChatHistory = (sectionId: string) => {
+  const [messages, setMessages] = useState<Message[]>([]);
+  
+  const CHAT_HISTORY_KEY = `my-code-chat-history-${sectionId}`;
+
+  useEffect(() => {
+    try {
+      const savedHistory = localStorage.getItem(CHAT_HISTORY_KEY);
+      if (savedHistory) {
+        setMessages(JSON.parse(savedHistory));
+      } else {
+        setMessages([]);
+      }
+    } catch (error) {
+      console.error("Failed to load chat history from localStorage", error);
+      setMessages([]);
+    }
+  }, [CHAT_HISTORY_KEY]);
+
+  const updateChatHistory = useCallback((newMessages: Message[]) => {
+    setMessages(newMessages);
+    if (newMessages.length > 0) {
+      localStorage.setItem(CHAT_HISTORY_KEY, JSON.stringify(newMessages));
+    } else {
+      localStorage.removeItem(CHAT_HISTORY_KEY);
+    }
+  }, [CHAT_HISTORY_KEY]);
+
+  return [messages, updateChatHistory] as const;
+};
\ No newline at end of file