diff --git a/src/Illuminate/Validation/ValidationRuleParser.php b/src/Illuminate/Validation/ValidationRuleParser.php
index 3af36ce8985e..7ce0f41a45fd 100644
--- a/src/Illuminate/Validation/ValidationRuleParser.php
+++ b/src/Illuminate/Validation/ValidationRuleParser.php
@@ -250,7 +250,7 @@ protected static function parseParameters($rule, $parameter)
     {
         $rule = strtolower($rule);
 
-        if ($rule === 'regex' || $rule === 'notregex') {
+        if ($rule === 'regex' || $rule === 'not_regex' || $rule === 'notregex') {
             return [$parameter];
         }