diff --git a/functions/src/index.ts b/functions/src/index.ts
index c84668e..244aa83 100644
--- a/functions/src/index.ts
+++ b/functions/src/index.ts
@@ -3,7 +3,8 @@ import express from "express";
 import { rateLimit } from "express-rate-limit";
 import admin from "firebase-admin";
 import { logger } from "firebase-functions";
-import { onRequest } from "firebase-functions/v2/https";
+import { HttpsError, onRequest } from "firebase-functions/v2/https";
+import { beforeUserCreated } from "firebase-functions/v2/identity";
 import helmet from "helmet";
 import serviceAccount from "./serviceAccountKey.json";
 
@@ -138,3 +139,32 @@ export const helloWorld = onRequest({ region: region }, (req, res) => {
   logger.info("Hello log!", { structuredData: true });
   res.send("Hello World!");
 });
+
+const db = admin.firestore();
+
+// アカウント作成時に実行される処理
+export const beforecreated = beforeUserCreated(
+  { region: region },
+  async (event) => {
+    const user = event.data;
+
+    if (!user) {
+      throw new HttpsError("invalid-argument", "No user data provided.");
+    }
+    const userId = user?.uid;
+    const name = user?.displayName || "No Name";
+
+    try {
+      await db.collection("user").doc(userId).set({
+        name: name,
+        streak: 0,
+        fcmToken: "",
+      });
+    } catch (error) {
+      logger.error(error);
+      throw new HttpsError("internal", "Error creating user data.");
+    }
+
+    return;
+  }
+);
diff --git a/src/app/firebase.ts b/src/app/firebase.ts
index b5b0853..c9df1ab 100644
--- a/src/app/firebase.ts
+++ b/src/app/firebase.ts
@@ -55,7 +55,7 @@ if (typeof window !== "undefined") {
       isTokenAutoRefreshEnabled: true,
     });
 
-    getToken(appCheck)
+    await getToken(appCheck)
       .then((token) => {
         console.log("App Check: Success");
         appCheckToken = token.token;
diff --git a/src/app/layout.tsx b/src/app/layout.tsx
index f29f3ea..8443975 100644
--- a/src/app/layout.tsx
+++ b/src/app/layout.tsx
@@ -39,6 +39,7 @@ export default function RootLayout({
         <link rel="icon" type="image/svg+xml" href="/appIcon.svg" />
         <link rel="apple-touch-icon" href="/icon512_maskable.png"></link>
         <meta name="theme-color" content="#2EC6FE" />
+        <meta name="description" content={description} />
 
         {/* Open Graph */}
         <meta property="og:title" content="TODO REAL" />
diff --git a/src/utils/API/User/createUser.ts b/src/utils/API/User/createUser.ts
deleted file mode 100644
index 0f57cc5..0000000
--- a/src/utils/API/User/createUser.ts
+++ /dev/null
@@ -1,25 +0,0 @@
-import { appCheckToken, functionsEndpoint } from "@/app/firebase";
-
-/**
- * Cloud FunctionsのAPIを呼び出して、ユーザー情報をFirestoreに登録する
- * AuthenticationのuserIdと/userのdocument IDは同じにする
- *
- * @param {string} name
- * @param {string} userId
- */
-export const createUser = async (name: string, userId: string) => {
-  const response = await fetch(`${functionsEndpoint}/user/`, {
-    method: "POST",
-    headers: {
-      "X-Firebase-AppCheck": appCheckToken,
-      "Content-Type": "application/json",
-    },
-    body: JSON.stringify({ userId, name }),
-  });
-
-  if (!response.ok) {
-    const status = response.status;
-    const data = await response.json();
-    throw new Error(`Error ${status}: ${data.message}`);
-  }
-};
diff --git a/src/utils/API/User/fetchUser.ts b/src/utils/API/User/fetchUser.ts
index 577f38a..5b5cfc6 100644
--- a/src/utils/API/User/fetchUser.ts
+++ b/src/utils/API/User/fetchUser.ts
@@ -33,7 +33,7 @@ export const fetchUserById = async (userId: string): Promise<User> => {
  * @return {*}
  */
 export const handleFetchUserError = (error: unknown) => {
-  let snackBarMessage = "初回ログインかユーザーデータが見つかりません";
+  let snackBarMessage = "ユーザーデータが見つかりません";
 
   if (error instanceof Error) {
     if (error.message.includes("404")) {
diff --git a/src/utils/Auth/signInWithGoogleAccount.ts b/src/utils/Auth/signInWithGoogleAccount.ts
index 0c508b7..8781fe7 100644
--- a/src/utils/Auth/signInWithGoogleAccount.ts
+++ b/src/utils/Auth/signInWithGoogleAccount.ts
@@ -1,29 +1,15 @@
 import { auth, googleProvider } from "@/app/firebase";
 import { showSnackBar } from "@/Components/SnackBar/SnackBar";
-import { createUser } from "@/utils/API/User/createUser";
-import { updateUser } from "@/utils/UserContext";
-import { getAdditionalUserInfo, signInWithPopup } from "firebase/auth";
+import { signInWithPopup } from "firebase/auth";
 
 /**
  * Firebase Authenticationを使ってGoogleアカウントでログインする
- * 初回ログインの時のみデータベースにユーザー情報を登録する
+ *
  *
  */
 export const signInWithGoogleAccount = async () => {
   try {
-    const result = await signInWithPopup(auth, googleProvider);
-
-    // 初めての時だけユーザー情報を登録する
-    if (getAdditionalUserInfo(result)?.isNewUser) {
-      // uidとdocument IDを一致させる
-      await createUser(result.user.displayName ?? "no name", result.user.uid);
-      updateUser({
-        userId: result.user.uid,
-        name: result.user.displayName ?? "no name",
-        loginType: "Google",
-        isMailVerified: result.user.emailVerified,
-      });
-    }
+    await signInWithPopup(auth, googleProvider);
 
     showSnackBar({
       message: "Googleアカウントでログインしました",
diff --git a/src/utils/Auth/signUpWithMail.tsx b/src/utils/Auth/signUpWithMail.tsx
index 1f30fdb..e739f6e 100644
--- a/src/utils/Auth/signUpWithMail.tsx
+++ b/src/utils/Auth/signUpWithMail.tsx
@@ -1,12 +1,11 @@
-import { auth } from "@/app/firebase";
+import { appCheckToken, auth, functionsEndpoint } from "@/app/firebase";
 import { showSnackBar } from "@/Components/SnackBar/SnackBar";
-import { createUser } from "@/utils/API/User/createUser";
-import { updateUser } from "@/utils/UserContext";
 import {
   createUserWithEmailAndPassword,
   sendEmailVerification,
   updateProfile,
 } from "firebase/auth";
+import { updateUser } from "../UserContext";
 
 /**
  * Firebase Authenticationを使ってメールでユーザーを作成し、生成されたuserIdをドキュメントIDとしてFirestoreにユーザー情報を登録する
@@ -33,8 +32,22 @@ export const signUpWithMail = async (
         console.error("プロファイル更新に失敗しました:", profileUpdateError);
       }
 
-      // userIdとdocument IDを一致させる
-      await createUser(name, user.uid);
+      // displayNameをFirestoreに登録
+      const response = await fetch(`${functionsEndpoint}/user/${user.uid}`, {
+        method: "PUT",
+        headers: {
+          "X-Firebase-AppCheck": appCheckToken,
+          "Content-Type": "application/json",
+        },
+        body: JSON.stringify({ name }),
+      });
+
+      if (!response.ok) {
+        const status = response.status;
+        const data = await response.json();
+        throw new Error(`Error ${status}: ${data.message}`);
+      }
+
       updateUser({
         userId: user.uid,
         name: name,
@@ -46,7 +59,7 @@ export const signUpWithMail = async (
       try {
         await sendEmailVerification(user);
       } catch (verificationError) {
-        console.error("failed to send email verification:", verificationError);
+        console.error("Failed to send email verification:", verificationError);
       }
 
       showSnackBar({
diff --git a/src/utils/UserContext.tsx b/src/utils/UserContext.tsx
index efd01b2..3d92941 100644
--- a/src/utils/UserContext.tsx
+++ b/src/utils/UserContext.tsx
@@ -85,8 +85,6 @@ export const UserProvider = ({ children }: Props) => {
 
         try {
           const userData = await fetchUserById(firebaseUser.uid);
-          // ユーザーデータを作成する前にfetchしようとして"User not found"になるので、postした場所でsetさせている
-          // "User not found"ではない(= 初回ログイン直後ではない)場合のみsetする
           if (userData.userId) {
             setUser({
               ...userData,