diff --git a/apps/calendar/index.php b/apps/calendar/index.php
index 352c295c437..a8ad4ab3356 100644
--- a/apps/calendar/index.php
+++ b/apps/calendar/index.php
@@ -5,7 +5,6 @@
  * later.
  * See the COPYING-README file.
  */
-DEFINE('DEBUG', TRUE);
 OCP\User::checkLoggedIn();
 OCP\App::checkAppEnabled('calendar');