diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 3e490fe8ba4..eccaeabde5e 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -997,6 +997,18 @@ impl<'a> DocumentMethods for JSRef<'a, Document> {
         Ok(Attr::new(window.r(), name, value, l_name, ns!(""), None, None))
     }
 
+    // http://dom.spec.whatwg.org/#dom-document-createattributens
+    fn CreateAttributeNS(self, namespace: Option<DOMString>, qualified_name: DOMString)
+                         -> Fallible<Temporary<Attr>> {
+        let (namespace, prefix, local_name) =
+            try!(validate_and_extract(namespace, &qualified_name));
+        let window = self.window.root();
+        let value = AttrValue::String("".to_owned());
+        let qualified_name = Atom::from_slice(&qualified_name);
+        Ok(Attr::new(window.r(), local_name, value, qualified_name,
+                     namespace, prefix, None))
+    }
+
     // http://dom.spec.whatwg.org/#dom-document-createdocumentfragment
     fn CreateDocumentFragment(self) -> Temporary<DocumentFragment> {
         DocumentFragment::new(self)
diff --git a/components/script/dom/webidls/Document.webidl b/components/script/dom/webidls/Document.webidl
index dea9b9c38f6..c57b09fff1b 100644
--- a/components/script/dom/webidls/Document.webidl
+++ b/components/script/dom/webidls/Document.webidl
@@ -40,14 +40,16 @@ interface Document : Node {
   [NewObject, Throws]
   ProcessingInstruction createProcessingInstruction(DOMString target, DOMString data);
 
-  [NewObject, Throws]
-  Attr createAttribute(DOMString localName);
-
   [NewObject, Throws]
   Node importNode(Node node, optional boolean deep = false);
   [Throws]
   Node adoptNode(Node node);
 
+  [NewObject, Throws]
+  Attr createAttribute(DOMString localName);
+  [NewObject, Throws]
+  Attr createAttributeNS(DOMString? namespace, DOMString localName);
+
   [NewObject, Throws]
   Event createEvent(DOMString interface_);
 
diff --git a/tests/wpt/metadata/dom/interfaces.html.ini b/tests/wpt/metadata/dom/interfaces.html.ini
index c3913ed9046..2c1b57f5f92 100644
--- a/tests/wpt/metadata/dom/interfaces.html.ini
+++ b/tests/wpt/metadata/dom/interfaces.html.ini
@@ -90,9 +90,6 @@
   [Document interface: operation importNode(Node,boolean)]
     expected: FAIL
 
-  [Document interface: operation createAttributeNS(DOMString,DOMString)]
-    expected: FAIL
-
   [Document interface: operation createNodeIterator(Node,unsigned long,NodeFilter)]
     expected: FAIL
 
@@ -141,9 +138,6 @@
   [Document interface: xmlDoc must inherit property "origin" with the proper type (3)]
     expected: FAIL
 
-  [Document interface: calling createAttributeNS(DOMString,DOMString) on xmlDoc with too few arguments must throw TypeError]
-    expected: FAIL
-
   [Document interface: calling createNodeIterator(Node,unsigned long,NodeFilter) on xmlDoc with too few arguments must throw TypeError]
     expected: FAIL
 
@@ -1020,9 +1014,6 @@
   [DOMTokenList interface object length]
     expected: FAIL
 
-  [Document interface: xmlDoc must inherit property "createAttributeNS" with the proper type (22)]
-    expected: FAIL
-
   [Document interface: xmlDoc must inherit property "createNodeIterator" with the proper type (25)]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/dom/interfaces.html.ini b/tests/wpt/metadata/html/dom/interfaces.html.ini
index 6bb217f0051..f91c0e52aeb 100644
--- a/tests/wpt/metadata/html/dom/interfaces.html.ini
+++ b/tests/wpt/metadata/html/dom/interfaces.html.ini
@@ -1035,12 +1035,6 @@
   [Document interface: document.implementation.createDocument(null, "", null) must inherit property "origin" with the proper type (3)]
     expected: FAIL
 
-  [Document interface: document.implementation.createDocument(null, "", null) must inherit property "createAttributeNS" with the proper type (22)]
-    expected: FAIL
-
-  [Document interface: calling createAttributeNS(DOMString,DOMString) on document.implementation.createDocument(null, "", null) with too few arguments must throw TypeError]
-    expected: FAIL
-
   [Document interface: document.implementation.createDocument(null, "", null) must inherit property "createNodeIterator" with the proper type (25)]
     expected: FAIL