diff --git a/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php b/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
index 6da68c7594544..b06c649885b56 100644
--- a/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
+++ b/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
@@ -208,7 +208,11 @@ protected function addRoute(RouteCollection $collection, object $annot, array $g
             }
             foreach ($paths as $locale => $path) {
                 if (preg_match(sprintf('/\{%s(?:<.*?>)?\}/', preg_quote($param->name)), $path)) {
-                    $defaults[$param->name] = $param->getDefaultValue();
+                    if (\is_scalar($defaultValue = $param->getDefaultValue()) || null === $defaultValue) {
+                        $defaults[$param->name] = $defaultValue;
+                    } elseif ($defaultValue instanceof \BackedEnum) {
+                        $defaults[$param->name] = $defaultValue->value;
+                    }
                     break;
                 }
             }
diff --git a/src/Symfony/Component/Routing/Tests/Fixtures/AnnotationFixtures/DefaultValueController.php b/src/Symfony/Component/Routing/Tests/Fixtures/AnnotationFixtures/DefaultValueController.php
index f7e38c290d2e7..c5e0c20d356e1 100644
--- a/src/Symfony/Component/Routing/Tests/Fixtures/AnnotationFixtures/DefaultValueController.php
+++ b/src/Symfony/Component/Routing/Tests/Fixtures/AnnotationFixtures/DefaultValueController.php
@@ -3,6 +3,8 @@
 namespace Symfony\Component\Routing\Tests\Fixtures\AnnotationFixtures;
 
 use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Component\Routing\Tests\Fixtures\Enum\TestIntBackedEnum;
+use Symfony\Component\Routing\Tests\Fixtures\Enum\TestStringBackedEnum;
 
 class DefaultValueController
 {
@@ -20,4 +22,18 @@ public function action($default = 'value')
     public function hello(string $name = 'World')
     {
     }
+
+    /**
+     * @Route("/enum/{default}", name="string_enum_action")
+     */
+    public function stringEnumAction(TestStringBackedEnum $default = TestStringBackedEnum::Diamonds)
+    {
+    }
+
+    /**
+     * @Route("/enum/{default<\d+>}", name="int_enum_action")
+     */
+    public function intEnumAction(TestIntBackedEnum $default = TestIntBackedEnum::Diamonds)
+    {
+    }
 }
diff --git a/src/Symfony/Component/Routing/Tests/Fixtures/AttributeFixtures/DefaultValueController.php b/src/Symfony/Component/Routing/Tests/Fixtures/AttributeFixtures/DefaultValueController.php
index 5bbfb0126dd2b..4d0df50698c22 100644
--- a/src/Symfony/Component/Routing/Tests/Fixtures/AttributeFixtures/DefaultValueController.php
+++ b/src/Symfony/Component/Routing/Tests/Fixtures/AttributeFixtures/DefaultValueController.php
@@ -3,6 +3,8 @@
 namespace Symfony\Component\Routing\Tests\Fixtures\AttributeFixtures;
 
 use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Component\Routing\Tests\Fixtures\Enum\TestIntBackedEnum;
+use Symfony\Component\Routing\Tests\Fixtures\Enum\TestStringBackedEnum;
 
 class DefaultValueController
 {
@@ -18,4 +20,14 @@ public function action($default = 'value')
     public function hello(string $name = 'World')
     {
     }
+
+    #[Route(path: '/enum/{default}', name: 'string_enum_action')]
+    public function stringEnumAction(TestStringBackedEnum $default = TestStringBackedEnum::Diamonds)
+    {
+    }
+
+    #[Route(path: '/enum/{default<\d+>}', name: 'int_enum_action')]
+    public function intEnumAction(TestIntBackedEnum $default = TestIntBackedEnum::Diamonds)
+    {
+    }
 }
diff --git a/src/Symfony/Component/Routing/Tests/Loader/AnnotationClassLoaderTestCase.php b/src/Symfony/Component/Routing/Tests/Loader/AnnotationClassLoaderTestCase.php
index b717d19609794..62a1d423441eb 100644
--- a/src/Symfony/Component/Routing/Tests/Loader/AnnotationClassLoaderTestCase.php
+++ b/src/Symfony/Component/Routing/Tests/Loader/AnnotationClassLoaderTestCase.php
@@ -104,11 +104,13 @@ public function testLocalizedPathRoutesWithExplicitPathPropety()
     public function testDefaultValuesForMethods()
     {
         $routes = $this->loader->load($this->getNamespace().'\DefaultValueController');
-        $this->assertCount(3, $routes);
+        $this->assertCount(5, $routes);
         $this->assertEquals('/{default}/path', $routes->get('action')->getPath());
         $this->assertEquals('value', $routes->get('action')->getDefault('default'));
         $this->assertEquals('Symfony', $routes->get('hello_with_default')->getDefault('name'));
         $this->assertEquals('World', $routes->get('hello_without_default')->getDefault('name'));
+        $this->assertEquals('diamonds', $routes->get('string_enum_action')->getDefault('default'));
+        $this->assertEquals(20, $routes->get('int_enum_action')->getDefault('default'));
     }
 
     public function testMethodActionControllers()