diff --git a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
index a31959e45655..986ccf0b81f9 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
@@ -299,7 +299,7 @@ private function parseDefaults(array &$content, string $file): array
     private function isUsingShortSyntax(array $service): bool
     {
         foreach ($service as $key => $value) {
-            if (\is_string($key) && ('' === $key || '$' !== $key[0])) {
+            if (\is_string($key) && ('' === $key || ('$' !== $key[0] && false === strpos($key, '\\')))) {
                 return false;
             }
         }
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_short_syntax.yml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_short_syntax.yml
new file mode 100644
index 000000000000..16ddb6bdf241
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_short_syntax.yml
@@ -0,0 +1,6 @@
+services:
+    foo_bar: [1, 2]
+
+    bar_foo:
+        $a: 'a'
+        App\Foo: 'foo'
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
index f40fc22cc345..eb6d01a19749 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
@@ -205,6 +205,17 @@ public function testLoadServices()
         $this->assertEquals(['decorated', 'decorated.pif-pouf', 5, ContainerInterface::IGNORE_ON_INVALID_REFERENCE], $services['decorator_service_with_name_and_priority_and_on_invalid']->getDecoratedService());
     }
 
+    public function testLoadShortSyntax()
+    {
+        $container = new ContainerBuilder();
+        $loader = new YamlFileLoader($container, new FileLocator(self::$fixturesPath.'/yaml'));
+        $loader->load('services_short_syntax.yml');
+        $services = $container->getDefinitions();
+
+        $this->assertSame([1, 2], $services['foo_bar']->getArguments());
+        $this->assertSame(['$a' => 'a', 'App\Foo' => 'foo'], $services['bar_foo']->getArguments());
+    }
+
     public function testDeprecatedAliases()
     {
         $container = new ContainerBuilder();