diff --git a/backend/app/Http/Controllers/Api/AuthenticationTrait.php b/backend/app/Http/Controllers/Api/AuthenticationTrait.php
index d49a61dd..278f1696 100644
--- a/backend/app/Http/Controllers/Api/AuthenticationTrait.php
+++ b/backend/app/Http/Controllers/Api/AuthenticationTrait.php
@@ -10,6 +10,18 @@ use Illuminate\Http\Request;
 // use App\Models\LoginLimits;
 
 trait AuthenticationTrait {
+    private function makeSession ($guard, $db) {
+        if (!session()->has($guard)) {
+            // 認証されたデータのpasswordとremember_token以外を把握する
+            unset($db['password']);
+            unset($db['remember_token']);
+            // セッションに保存する
+            session()->put($guard, $db);
+        }
+
+        return $db;
+    }
+
     public function login (Request $r) {
         // if (null === $r->server('HTTP_USER_AGENT')) {
         //     return ['status_code' => 400, 'error_message' => ['不正なuser_agent。']];
@@ -24,6 +36,15 @@ trait AuthenticationTrait {
         //     }
         // }
 
+        if (isset($_COOKIE['remember_token']) && !is_null($_COOKIE['remember_token'])) { // クッキーがある場合
+            if (null === ($get = $this->getModel()->where('remember_token', $_COOKIE['remember_token'])->first())) { // トークンがある場合
+                // セッションを想像する
+                $login_user_datum = $this->makeSession($this->getGuard(), $get->toArray());
+
+                return ['status_code' => 200, 'params' => ['id' => $login_user_datum['id']]];
+            }
+        }
+
         if ($this->getGuard() == 'children') {
             Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
                 return $this->telsize($value);
@@ -66,13 +87,15 @@ trait AuthenticationTrait {
         if (Session::has('admins'))   Session::forget('admins');
 
         // セッションを想像する
-        $guard = $this->getGuard();
-        if (!$r->session()->has($guard)) {
-            // 認証されたデータのpassword以外を把握する
-            $login_user_datum = $get->toArray();
-            unset($login_user_datum['password']);
-            // セッションに保存する
-            $r->session()->put($guard, $login_user_datum);
+        $login_user_datum = $this->makeSession($this->getGuard(), $get->toArray());
+
+        if ($r->remember_token) {
+            $token = bin2hex(random_bytes(24));
+
+            try {
+                $this->getGuard()->where('id', $login_user_datum['id'])->update(['remember_token' => $token]);
+                setcookie('remember_token', $token, time()+157788000, '/', $_SERVER['HTTP_HOST'], 0, 1);
+            }
         }
 
         return ['status_code' => 200, 'params' => ['id' => $login_user_datum['id']]];
@@ -80,7 +103,14 @@ trait AuthenticationTrait {
 
     public function logout () {
         // セッションを破壊すると、ログイン画面に移転する。
-        Session::forget($this->getGuard());
+        $guard = $this->getGuard();
+        if (null !== $rem = $this->getModel()->select('remember_token')->where('id', Session::get()['id'])->first()) {
+            $this->getModel()->where('id', Session::get()['id'])->update(['remember_token' => null]);
+            unset($_COOKIE['remember_token']);
+            setcookie('remember_token', '', time() - 3600, '/', $_SERVER['HTTP_HOST'], 0, 1);
+        }
+
+        Session::forget($guard);
 
         return redirect(request()->route()->action['prefix'].'/login');
     }
diff --git a/backend/database/migrations/2021_08_10_045054_create_admins_table.php b/backend/database/migrations/2021_08_10_045054_create_admins_table.php
index 11cc5871..a55346e2 100644
--- a/backend/database/migrations/2021_08_10_045054_create_admins_table.php
+++ b/backend/database/migrations/2021_08_10_045054_create_admins_table.php
@@ -17,6 +17,7 @@ class CreateAdminsTable extends Migration
             $table->id();
             $table->string('email', 72)->unique();
             $table->string('password', 72);
+            $table->string('remember_token', 255)->nullable();
             $table->timestamps();
         });
     }
diff --git a/backend/database/migrations/2021_08_12_054526_create_fathers_table.php b/backend/database/migrations/2021_08_12_054526_create_fathers_table.php
index 3cf52a9c..a4e8559d 100644
--- a/backend/database/migrations/2021_08_12_054526_create_fathers_table.php
+++ b/backend/database/migrations/2021_08_12_054526_create_fathers_table.php
@@ -17,6 +17,7 @@ class CreateFathersTable extends Migration
             $table->id();
             $table->string('email', 255)->unique();
             $table->string('password', 72);
+            $table->string('remember_token', 255)->nullable();
             $table->string('company', 100);
             $table->string('image', 100)->nullable();
             $table->string('profile', 1000)->nullable();
diff --git a/backend/database/migrations/2021_08_13_042143_create_children_table.php b/backend/database/migrations/2021_08_13_042143_create_children_table.php
index dc2699cf..931e1a49 100644
--- a/backend/database/migrations/2021_08_13_042143_create_children_table.php
+++ b/backend/database/migrations/2021_08_13_042143_create_children_table.php
@@ -19,6 +19,7 @@ class CreateChildrenTable extends Migration
             $table->string('email', 72)->unique();
             $table->string('tel', 11)->unique();
             $table->string('password', 255);
+            $table->string('remember_token', 255)->nullable();
             $table->string('last_name', 100);
             $table->string('first_name', 100);
             $table->string('image', 100)->nullable();