diff --git a/backend/app/Http/Controllers/Api/MeetingsController.php b/backend/app/Http/Controllers/Api/MeetingsController.php
index 3d2b419b..1a2f8134 100644
--- a/backend/app/Http/Controllers/Api/MeetingsController.php
+++ b/backend/app/Http/Controllers/Api/MeetingsController.php
@@ -848,10 +848,10 @@ class MeetingsController extends Controller {
 
     public function updateMemo (Request $r) {
         if (!isset($r->meeting_id)) {
-            return ['status_code' => 400, 'error_messages' => ['ミーティングの登録に失敗しました。']];
+            return ['status_code' => 400, 'error_messages' => ['メモの更新に失敗しました。']];
         }
 
-        $validate = Validator::make($r->all(), ['memo' => 'max:2000']);
+        $validate = Validator::make($r->all(), ['memo' => 'required|max:2000']);
 
         if ($validate->fails()) {
             return ['status_code' => 422, 'error_messages' => $validate->errors()];