diff --git a/src/JsonSerializationVisitor.php b/src/JsonSerializationVisitor.php
index c5b729acd..dcd345508 100644
--- a/src/JsonSerializationVisitor.php
+++ b/src/JsonSerializationVisitor.php
@@ -167,8 +167,8 @@ public function visitProperty(PropertyMetadata $metadata, $data, Context $contex
         $k = $this->namingStrategy->translateName($metadata);
 
         if ($metadata->inline) {
-            if (is_array($v)) {
-                $this->data = array_merge($this->data, $v);
+            if (is_array($v) || ($v instanceof \ArrayObject)) {
+                $this->data = array_merge($this->data, (array) $v);
             }
         } else {
             $this->data[$k] = $v;
diff --git a/tests/JMS/Serializer/Tests/Fixtures/ObjectWithInlineArray.php b/tests/JMS/Serializer/Tests/Fixtures/ObjectWithInlineArray.php
new file mode 100644
index 000000000..866ebae39
--- /dev/null
+++ b/tests/JMS/Serializer/Tests/Fixtures/ObjectWithInlineArray.php
@@ -0,0 +1,24 @@
+<?php
+
+namespace JMS\Serializer\Tests\Fixtures;
+
+use JMS\Serializer\Annotation as Serializer;
+
+final class ObjectWithInlineArray
+{
+    /**
+     * @Serializer\Inline()
+     * @Serializer\Type("array<string,string>")
+     */
+    public $array;
+
+    /**
+     * @param array $array
+     */
+    public function __construct(array $array)
+    {
+        $this->array = $array;
+    }
+
+
+}
diff --git a/tests/Serializer/JsonSerializationTest.php b/tests/Serializer/JsonSerializationTest.php
index 59f891339..83c96c4b6 100644
--- a/tests/Serializer/JsonSerializationTest.php
+++ b/tests/Serializer/JsonSerializationTest.php
@@ -27,6 +27,7 @@
 use JMS\Serializer\Tests\Fixtures\Author;
 use JMS\Serializer\Tests\Fixtures\AuthorList;
 use JMS\Serializer\Tests\Fixtures\ObjectWithEmptyArrayAndHash;
+use JMS\Serializer\Tests\Fixtures\ObjectWithInlineArray;
 use JMS\Serializer\Tests\Fixtures\Tag;
 use JMS\Serializer\VisitorInterface;
 
@@ -280,6 +281,13 @@ public function testSerializeArrayWithEmptyObject()
         $this->assertEquals('[{}]', $this->serialize(array(new \stdClass())));
     }
 
+    public function testInlineArray()
+    {
+        $object = new ObjectWithInlineArray(['a' => 'b', 'c' => 'd']);
+
+        $this->assertEquals('{"a":"b","c":"d"}', $this->serialize($object));
+    }
+
     public function testSerializeRootArrayWithDefinedKeys()
     {
         $author1 = new Author("Jim");