diff --git a/src/components/script/dom/worker.rs b/src/components/script/dom/worker.rs
index 6c79525a139..5a62f1c37f4 100644
--- a/src/components/script/dom/worker.rs
+++ b/src/components/script/dom/worker.rs
@@ -2,13 +2,14 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use dom::bindings::error::{Fallible, Security};
+use dom::bindings::error::{Fallible, Security, Syntax};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Temporary;
 use dom::bindings::utils::{Reflectable, Reflector};
 use dom::eventtarget::EventTarget;
 
 use servo_util::str::DOMString;
+use servo_util::url::try_parse_url;
 
 #[deriving(Encodable)]
 pub struct Worker {
@@ -16,7 +17,13 @@ pub struct Worker {
 }
 
 impl Worker {
-    pub fn Constructor(_global: &GlobalRef, _scriptURL: DOMString) -> Fallible<Temporary<Worker>> {
+    pub fn Constructor(global: &GlobalRef, scriptURL: DOMString) -> Fallible<Temporary<Worker>> {
+        // Step 2-4.
+        let _worker_url = match try_parse_url(scriptURL.as_slice(), Some(global.get_url())) {
+            Ok(url) => url,
+            Err(_) => return Err(Syntax),
+        };
+
         Err(Security)
     }
 }