diff --git a/plugins/bc-mail/src/Controller/Api/MailMessagesController.php b/plugins/bc-mail/src/Controller/Api/MailMessagesController.php
index 6f8fcc0257..a7485bdc00 100644
--- a/plugins/bc-mail/src/Controller/Api/MailMessagesController.php
+++ b/plugins/bc-mail/src/Controller/Api/MailMessagesController.php
@@ -36,6 +36,7 @@ class MailMessagesController extends BcApiController
      * @return \Cake\Http\Response|void
      * @checked
      * @noTodo
+     * @unitTest
      */
     public function beforeFilter(EventInterface $event)
     {
diff --git a/plugins/bc-mail/tests/TestCase/Controller/Api/Admin/MailMessagesControllerTest.php b/plugins/bc-mail/tests/TestCase/Controller/Api/Admin/MailMessagesControllerTest.php
index 99f9a1c342..71b6758e2b 100644
--- a/plugins/bc-mail/tests/TestCase/Controller/Api/Admin/MailMessagesControllerTest.php
+++ b/plugins/bc-mail/tests/TestCase/Controller/Api/Admin/MailMessagesControllerTest.php
@@ -15,9 +15,11 @@
 use BaserCore\Test\Factory\ContentFactory;
 use BaserCore\Test\Scenario\InitAppScenario;
 use BaserCore\TestSuite\BcTestCase;
+use BcMail\Controller\Api\MailMessagesController;
 use BcMail\Service\MailMessagesServiceInterface;
 use BcMail\Test\Factory\MailContentFactory;
 use BcMail\Test\Scenario\MailContentsScenario;
+use Cake\Event\Event;
 use Cake\ORM\Entity;
 use Cake\ORM\TableRegistry;
 use Cake\TestSuite\IntegrationTestTrait;
@@ -56,6 +58,19 @@ public function tearDown(): void
         parent::tearDown();
     }
 
+
+    /**
+     * test beforeFilter
+     */
+    public function testBeforeFilter()
+    {
+        $this->MailMessagesController = new MailMessagesController($this->getRequest());
+        $event = new Event('Controller.beforeFilter', $this->MailMessagesController);
+        $this->MailMessagesController->beforeFilter($event);
+        $config = $this->MailMessagesController->FormProtection->getConfig('validate');
+        $this->assertFalse($config);
+    }
+
     /**
      * [API] 受信メール一覧
      */