diff --git a/ModelDescriber/FormModelDescriber.php b/ModelDescriber/FormModelDescriber.php
index 74e3370..3cbebf8 100644
--- a/ModelDescriber/FormModelDescriber.php
+++ b/ModelDescriber/FormModelDescriber.php
@@ -225,7 +225,15 @@ final class FormModelDescriber implements ModelDescriberInterface, ModelRegistry
         do {
             $class = get_class($type->getInnerType());
 
-            if (FormType::class !== $class && 0 === strpos($class, 'Symfony\Component\Form\Extension\Core\Type\\')) {
+            if (FormType::class === $class) {
+                return null;
+            }
+
+            if ('entity' === $type->getBlockPrefix()) {
+                return $type;
+            }
+
+            if (0 === strpos($class, 'Symfony\Component\Form\Extension\Core\Type\\')) {
                 return $type;
             }
         } while ($type = $type->getParent());
diff --git a/Tests/Functional/Form/EntityType.php b/Tests/Functional/Form/EntityType.php
new file mode 100644
index 0000000..c50de22
--- /dev/null
+++ b/Tests/Functional/Form/EntityType.php
@@ -0,0 +1,31 @@
+<?php
+
+/*
+ * This file is part of the NelmioApiDocBundle package.
+ *
+ * (c) Nelmio
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Nelmio\ApiDocBundle\Tests\Functional\Form;
+
+use Symfony\Component\Form\AbstractType;
+use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
+use Symfony\Component\OptionsResolver\OptionsResolver;
+
+class EntityType extends AbstractType
+{
+    public function configureOptions(OptionsResolver $resolver)
+    {
+        $resolver
+            ->setDefault('multiple', false)
+            ->setRequired('class');
+    }
+
+    public function getParent(): string
+    {
+        return ChoiceType::class;
+    }
+}
diff --git a/Tests/Functional/Form/UserType.php b/Tests/Functional/Form/UserType.php
index f829eee..48e6028 100644
--- a/Tests/Functional/Form/UserType.php
+++ b/Tests/Functional/Form/UserType.php
@@ -36,6 +36,7 @@ class UserType extends AbstractType
                 'required' => false,
             ])
             ->add('quz', DummyType::class, ['documentation' => ['type' => 'string', 'description' => 'User type.'], 'required' => false])
+            ->add('entity', EntityType::class, ['class' => 'Entity'])
             ->add('extended_builtin', ExtendedBuiltinType::class, ['required_option' => 'foo']);
     }
 
diff --git a/Tests/Functional/FunctionalTest.php b/Tests/Functional/FunctionalTest.php
index b17decf..e53274b 100644
--- a/Tests/Functional/FunctionalTest.php
+++ b/Tests/Functional/FunctionalTest.php
@@ -243,12 +243,16 @@ class FunctionalTest extends WebTestCase
                     'type' => 'string',
                     'description' => 'User type.',
                 ],
+                'entity' => [
+                    'type' => 'string',
+                    'format' => 'Entity id',
+                ],
                 'extended_builtin' => [
                     'type' => 'string',
                     'enum' => ['foo', 'bar'],
                 ],
             ],
-            'required' => ['dummy', 'dummies', 'extended_builtin'],
+            'required' => ['dummy', 'dummies', 'entity', 'extended_builtin'],
         ], $this->getModel('UserType')->toArray());
 
         $this->assertEquals([