diff --git a/install-dev/models/database.php b/install-dev/models/database.php
index 4e7dd4f50..fc59d5eed 100644
--- a/install-dev/models/database.php
+++ b/install-dev/models/database.php
@@ -53,7 +53,7 @@ class InstallModelDatabase extends InstallAbstractModel
 		if (!$login)
 			$errors[] = $this->language->l('You must enter a database login');
 
-		if (!$prefix || !Validate::isTablePrefix($prefix))
+		if ($prefix && !Validate::isTablePrefix($prefix))
 			$errors[] = $this->language->l('Tables prefix is invalid');
 
 		if (!Validate::isMySQLEngine($engine))