diff --git a/src/Symfony/Bridge/Doctrine/Middleware/IdleConnection/Listener.php b/src/Symfony/Bridge/Doctrine/Middleware/IdleConnection/Listener.php
index 11f7053c5f702..ad570821d7c76 100644
--- a/src/Symfony/Bridge/Doctrine/Middleware/IdleConnection/Listener.php
+++ b/src/Symfony/Bridge/Doctrine/Middleware/IdleConnection/Listener.php
@@ -14,6 +14,7 @@
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\HttpKernel\Event\RequestEvent;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
 
 final class Listener implements EventSubscriberInterface
@@ -29,6 +30,9 @@ public function __construct(
 
     public function onKernelRequest(RequestEvent $event): void
     {
+        if (HttpKernelInterface::MAIN_REQUEST !== $event->getRequestType()) {
+            return;
+        }
         $timestamp = time();
 
         foreach ($this->connectionExpiries as $name => $expiry) {
diff --git a/src/Symfony/Bridge/Doctrine/Tests/Middleware/IdleConnection/ListenerTest.php b/src/Symfony/Bridge/Doctrine/Tests/Middleware/IdleConnection/ListenerTest.php
index 099ab48777133..72fa7e068f67c 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/Middleware/IdleConnection/ListenerTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/Middleware/IdleConnection/ListenerTest.php
@@ -9,13 +9,14 @@
  * file that was distributed with this source code.
  */
 
-namespace Middleware\IdleConnection;
+namespace Symfony\Bridge\Doctrine\Tests\Middleware\IdleConnection;
 
 use Doctrine\DBAL\Connection as ConnectionInterface;
 use PHPUnit\Framework\TestCase;
 use Symfony\Bridge\Doctrine\Middleware\IdleConnection\Listener;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpKernel\Event\RequestEvent;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
 
 class ListenerTest extends TestCase
 {
@@ -34,10 +35,24 @@ public function testOnKernelRequest()
             ->willReturn($connectionOneMock);
 
         $listener = new Listener($connectionExpiries, $containerMock);
+        $event = $this->createMock(RequestEvent::class);
+        $event->method('getRequestType')->willReturn(HttpKernelInterface::MAIN_REQUEST);
 
-        $listener->onKernelRequest($this->createMock(RequestEvent::class));
+        $listener->onKernelRequest($event);
 
         $this->assertArrayNotHasKey('connectionone', (array) $connectionExpiries);
         $this->assertArrayHasKey('connectiontwo', (array) $connectionExpiries);
     }
+
+    public function testOnKernelRequestShouldSkipSubrequests()
+    {
+        self::expectNotToPerformAssertions();
+        $arrayObj = $this->createMock(\ArrayObject::class);
+        $arrayObj->method('getIterator')->willThrowException(new \Exception('Invalid behavior'));
+        $listener = new Listener($arrayObj, $this->createMock(ContainerInterface::class));
+
+        $event = $this->createMock(RequestEvent::class);
+        $event->method('getRequestType')->willReturn(HttpKernelInterface::SUB_REQUEST);
+        $listener->onKernelRequest($event);
+    }
 }