diff --git a/core/modules/serialization/src/Normalizer/EntityReferenceFieldItemNormalizer.php b/core/modules/serialization/src/Normalizer/EntityReferenceFieldItemNormalizer.php
index 5298d6a..4515f31 100644
--- a/core/modules/serialization/src/Normalizer/EntityReferenceFieldItemNormalizer.php
+++ b/core/modules/serialization/src/Normalizer/EntityReferenceFieldItemNormalizer.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\serialization\Normalizer;
 
+use Doctrine\Common\Proxy\Exception\InvalidArgumentException;
 use Drupal\Core\Entity\EntityRepositoryInterface;
 use Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem;
 use Symfony\Component\Serializer\Exception\UnexpectedValueException;
@@ -64,12 +65,19 @@ protected function constructValue($data, $context) {
     if (!empty($data['target_uuid'])) {
       /** @var \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem $field_item */
       $field_item = $context['target_instance'];
-      $target_type = $field_item->getFieldDefinition()->getSetting('target_type');
+      if (!empty($data['target_type'])) {
+        $target_type = $field_item->getFieldDefinition()->getSetting('target_type');
+      }
       if (!empty($data['target_type']) && $target_type !== $data['target_type']) {
         throw new UnexpectedValueException(sprintf('The field "%s" property "target_type" must be set to "%s" or omitted.', $field_item->getFieldDefinition()->getName(), $target_type));
       }
-      $entity = $this->entityRepository->loadEntityByUuid($target_type, $data['target_uuid']);
-      return ['target_id' => $entity->id()];
+      if ($entity = $this->entityRepository->loadEntityByUuid($data['target_type'], $data['target_uuid'])) {
+        return ['target_id' => $entity->id()];
+      }
+      else {
+        // Unable to load entity by uuid.
+        throw new InvalidArgumentException(sprintf('"%s" is not a valid UUID.', $data['target_uuid']));
+      }
     }
     return parent::constructValue($data, $context);
   }
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
index 519963f..e12b837 100644
--- a/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
@@ -199,6 +199,26 @@ public function testDenormalizeWithUuidWithIncorrectType() {
 
   /**
    * @covers ::denormalize
+   *
+   * @expectedException \Doctrine\Common\Proxy\Exception\InvalidArgumentException
+   * @expectedExceptionMessage "unique-but-none-non-existent" is not a valid UUID.
+   */
+  public function testDenormalizeWithTypeWithIncorrectUuid() {
+    $data = [
+      'target_id' => ['value' => 'test'],
+      'target_type' => 'test_type',
+      'target_uuid' => 'unique-but-none-non-existent',
+    ];
+    $this->entityRepository
+      ->loadEntityByUuid($data['target_type'], $data['target_uuid'])
+      ->willReturn(NULL)
+      ->shouldBeCalled();
+
+    $this->assertDenormalize($data);
+  }
+
+  /**
+   * @covers ::denormalize
    */
   public function testDenormalizeWithId() {
     $data = [