diff --git a/wp-admin/admin-ajax.php b/wp-admin/admin-ajax.php
index 38f7dd97d7..3454dd9c4f 100644
--- a/wp-admin/admin-ajax.php
+++ b/wp-admin/admin-ajax.php
@@ -13,6 +13,7 @@
  */
 define('DOING_AJAX', true);
 define('WP_ADMIN', true);
+define('WP_SHOW_ADMIN_BAR' , false);
 
 if ( ! isset( $_REQUEST['action'] ) )
 	die('-1');