diff --git a/admin/report/simpletest/index.php b/admin/report/simpletest/index.php
index d7070c790f1..569255eb162 100644
--- a/admin/report/simpletest/index.php
+++ b/admin/report/simpletest/index.php
@@ -19,9 +19,6 @@ require_once('ex_reporter.php');
 require_login();
 require_capability('moodle/site:config', get_context_instance(CONTEXT_SYSTEM));
 
-/* The UNITTEST constant can be checked elsewhere if you need to know
- * when your code is being run as part of a unit test. */
-define('UNITTEST', true);
 $langfile = 'simpletest';
 
 // CGI arguments