diff --git a/src/Api/IdentifiersExtractor.php b/src/Api/IdentifiersExtractor.php
index f7f7dc65b85..c356d870b37 100644
--- a/src/Api/IdentifiersExtractor.php
+++ b/src/Api/IdentifiersExtractor.php
@@ -57,6 +57,10 @@ public function getIdentifiersFromResourceClass(string $resourceClass): array
             }
         }
 
+        if (!$identifiers) {
+            throw new RuntimeException(sprintf('No identifier defined "%s". You should add #[\ApiPlatform\Core\Annotation\ApiProperty(identifier: true)]" on the property identifying the resource."', $resourceClass));
+        }
+
         return $identifiers;
     }
 
diff --git a/tests/Api/IdentifiersExtractorTest.php b/tests/Api/IdentifiersExtractorTest.php
index 24237943b87..ac1abb415a4 100644
--- a/tests/Api/IdentifiersExtractorTest.php
+++ b/tests/Api/IdentifiersExtractorTest.php
@@ -202,6 +202,20 @@ public function testGetsIdentifiersFromCorrectResourceClass(): void
         $this->assertSame(['foo' => 'woot'], $identifiersExtractor->getIdentifiersFromItem($item));
     }
 
+    public function testNoIdentifiers(): void
+    {
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage('No identifier defined "ApiPlatform\\Core\\Tests\\Fixtures\\TestBundle\\Entity\\Dummy". You should add #[\ApiPlatform\Core\Annotation\ApiProperty(identifier: true)]" on the property identifying the resource.');
+        $propertyNameCollectionFactoryProphecy = $this->prophesize(PropertyNameCollectionFactoryInterface::class);
+        $propertyNameCollectionFactoryProphecy->create(Dummy::class)->willReturn(new PropertyNameCollection(['foo']));
+        $propertyMetadataFactoryProphecy = $this->prophesize(PropertyMetadataFactoryInterface::class);
+        $propertyMetadataFactoryProphecy->create(Dummy::class, 'foo')->willReturn(new PropertyMetadata());
+        $resourceClassResolverProphecy = $this->prophesize(ResourceClassResolverInterface::class);
+        $identifiersExtractor = new IdentifiersExtractor($propertyNameCollectionFactoryProphecy->reveal(), $propertyMetadataFactoryProphecy->reveal(), null, $resourceClassResolverProphecy->reveal());
+
+        $identifiersExtractor->getIdentifiersFromResourceClass(Dummy::class);
+    }
+
     /**
      * @group legacy
      * @expectedDeprecation Not injecting ApiPlatform\Core\Api\ResourceClassResolverInterface in the IdentifiersExtractor might introduce cache issues with object identifiers.
diff --git a/tests/Fixtures/TestBundle/Entity/DummyForAdditionalFieldsInput.php b/tests/Fixtures/TestBundle/Entity/DummyForAdditionalFieldsInput.php
index 58a061645ef..8564bb3c468 100644
--- a/tests/Fixtures/TestBundle/Entity/DummyForAdditionalFieldsInput.php
+++ b/tests/Fixtures/TestBundle/Entity/DummyForAdditionalFieldsInput.php
@@ -13,6 +13,7 @@
 
 namespace ApiPlatform\Core\Tests\Fixtures\TestBundle\Entity;
 
+use ApiPlatform\Core\Annotation\ApiProperty;
 use ApiPlatform\Core\Annotation\ApiResource;
 
 /**
@@ -20,6 +21,11 @@
  */
 final class DummyForAdditionalFieldsInput
 {
+    /**
+     * @ApiProperty(identifier=true)
+     */
+    public $id;
+
     private $dummyName;
 
     public function __construct(string $dummyName)
diff --git a/tests/Fixtures/TestBundle/Model/ResourceBarInterface.php b/tests/Fixtures/TestBundle/Model/ResourceBarInterface.php
index 01d46d9e1b5..543f76195a3 100644
--- a/tests/Fixtures/TestBundle/Model/ResourceBarInterface.php
+++ b/tests/Fixtures/TestBundle/Model/ResourceBarInterface.php
@@ -13,7 +13,12 @@
 
 namespace ApiPlatform\Core\Tests\Fixtures\TestBundle\Model;
 
+use ApiPlatform\Core\Annotation\ApiProperty;
+
 interface ResourceBarInterface
 {
+    /**
+     * @ApiProperty(identifier=true)
+     */
     public function getBar(): ?string;
 }