diff --git a/plugins/bc-mail/src/Controller/Admin/MailContentsController.php b/plugins/bc-mail/src/Controller/Admin/MailContentsController.php
index 75d4da3a1f..0a9af8693c 100644
--- a/plugins/bc-mail/src/Controller/Admin/MailContentsController.php
+++ b/plugins/bc-mail/src/Controller/Admin/MailContentsController.php
@@ -99,6 +99,7 @@ public function edit(MailContentsAdminServiceInterface $service, int $id)
      * @return Response
      * @checked
      * @noTodo
+     * @unitTest
      */
     private function redirectEditMail($template)
     {
diff --git a/plugins/bc-mail/tests/TestCase/Controller/Admin/MailContentsControllerTest.php b/plugins/bc-mail/tests/TestCase/Controller/Admin/MailContentsControllerTest.php
index d67bbbcb5c..7594658a48 100644
--- a/plugins/bc-mail/tests/TestCase/Controller/Admin/MailContentsControllerTest.php
+++ b/plugins/bc-mail/tests/TestCase/Controller/Admin/MailContentsControllerTest.php
@@ -98,7 +98,12 @@ public function testAdmin_edit()
      */
     public function test_redirectEditMail()
     {
-        $this->markTestIncomplete('このテストは、まだ実装されていません。');
+        $rs = $this->execPrivateMethod($this->MailContentsController, 'redirectEditMail', ['default']);
+        $this->assertEquals(302, $rs->getStatusCode());
+        $this->assertEquals(
+            ['https://localhost/baser/admin/bc-theme-file/theme_files/edit/BcFront/BcMail/email/text/default.php'],
+            $rs->getHeader('Location')
+        );
     }
 
     /**