diff --git a/core/lib/Drupal/Component/Utility/Unicode.php b/core/lib/Drupal/Component/Utility/Unicode.php
index 50e692104195439ff3e4e26fb89bcd42be917c5c..3217aa35454db9fe8afb429d67f42a33882941c5 100644
--- a/core/lib/Drupal/Component/Utility/Unicode.php
+++ b/core/lib/Drupal/Component/Utility/Unicode.php
@@ -131,9 +131,6 @@ public static function check() {
     }
 
     // Check mbstring configuration.
-    if (ini_get('mbstring.func_overload') != 0) {
-      return 'mbstring.func_overload';
-    }
     if (ini_get('mbstring.encoding_translation') != 0) {
       return 'mbstring.encoding_translation';
     }
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 3f252f7653690654bf85b9056c7435456f84ee2b..41d0b4fe30addb72541de9722c4404e4fe37a24c 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -1204,10 +1204,6 @@ function system_requirements($phase) {
       $requirements['unicode']['description'] = t('Operations on Unicode strings are emulated on a best-effort basis. Install the <a href="http://php.net/mbstring">PHP mbstring extension</a> for improved Unicode support.');
       break;
 
-    case 'mbstring.func_overload':
-      $requirements['unicode']['description'] = t('Multibyte string function overloading in PHP is active and must be disabled. Check the php.ini <em>mbstring.func_overload</em> setting. Please refer to the <a href="http://php.net/mbstring">PHP mbstring documentation</a> for more information.');
-      break;
-
     case 'mbstring.encoding_translation':
       $requirements['unicode']['description'] = t('Multibyte string input conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.encoding_translation</em> setting. Please refer to the <a href="http://php.net/mbstring">PHP mbstring documentation</a> for more information.');
       break;