diff --git a/linebot/app.py b/linebot/app.py
index 1474df3..9a68d53 100644
--- a/linebot/app.py
+++ b/linebot/app.py
@@ -7,23 +7,67 @@
 
 # ライブラリのインポート
 from flask import Flask, request, abort
-from linebot.models import (MessageEvent, TextMessage)
-from linebot import (LineBotApi, WebhookHandler)
-from linebot.exceptions import (InvalidSignatureError)
 
-# Flaskのインスタンス
-app = Flask(__name__)
+from linebot.v3 import (
+    WebhookHandler
+)
+from linebot.v3.exceptions import (
+    InvalidSignatureError
+)
+from linebot.v3.messaging import (
+    Configuration,
+    ApiClient,
+    MessagingApi,
+    ReplyMessageRequest,
+    TextMessage
+)
+from linebot.v3.webhooks import (
+    MessageEvent,
+    TextMessageContent
+)
 
 import json
 
-
 # config.jsonから情報を取得
 with open("./config.json", "r", encoding="utf8") as file:
     info_config = json.load(file)
 
-LINE_BOT_API = LineBotApi(info_config["LINE_CHANNEL_ACCESS_TOKEN"])
+configuration = Configuration(access_token=info_config["LINE_CHANNEL_ACCESS_TOKEN"])
+handler = WebhookHandler(info_config["LINE_CHANNEL_SECRET"])
 
-HANDLER = WebhookHandler(info_config["LINE_CHANNEL_SECRET"])
+app = Flask(__name__)
 
 SEARCH_WORD = ["お腹すいた"]
 
+@app.route("/callback", methods=['POST'])
+def callback():
+    # get X-Line-Signature header value
+    signature = request.headers['X-Line-Signature']
+
+    # get request body as text
+    body = request.get_data(as_text=True)
+    app.logger.info("Request body: " + body)
+
+    # handle webhook body
+    try:
+        handler.handle(body, signature)
+    except InvalidSignatureError:
+        app.logger.info("Invalid signature. Please check your channel access token/channel secret.")
+        abort(400)
+
+    return 'OK'
+
+
+@handler.add(MessageEvent, message=TextMessageContent)
+def handle_message(event):
+    with ApiClient(configuration) as api_client:
+        line_bot_api = MessagingApi(api_client)
+        line_bot_api.reply_message_with_http_info(
+            ReplyMessageRequest(
+                reply_token=event.reply_token,
+                messages=[TextMessage(text=event.message.text)]
+            )
+        )
+
+if __name__ == "__main__":
+    app.run()
\ No newline at end of file