diff --git a/src/Symfony/Component/EventDispatcher/DependencyInjection/RegisterListenersPass.php b/src/Symfony/Component/EventDispatcher/DependencyInjection/RegisterListenersPass.php
index 7820d35c31..2bbebb7d6f 100644
--- a/src/Symfony/Component/EventDispatcher/DependencyInjection/RegisterListenersPass.php
+++ b/src/Symfony/Component/EventDispatcher/DependencyInjection/RegisterListenersPass.php
@@ -16,7 +16,6 @@ use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
 use Symfony\Component\DependencyInjection\Reference;
-use Symfony\Component\EventDispatcher\Event as LegacyEvent;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Contracts\EventDispatcher\Event;
@@ -141,7 +140,6 @@ class RegisterListenersPass implements CompilerPassInterface
             || !($type = $m->getParameters()[0]->getType())
             || $type->isBuiltin()
             || Event::class === ($name = $type->getName())
-            || LegacyEvent::class === $name
         ) {
             throw new InvalidArgumentException(sprintf('Service "%s" must define the "event" attribute on "%s" tags.', $id, $this->listenerTag));
         }