diff --git a/lib/uv.sw.js b/lib/uv.sw.js
index 8a72003..90e3724 100644
--- a/lib/uv.sw.js
+++ b/lib/uv.sw.js
@@ -96,7 +96,7 @@ class UVServiceWorker extends EventEmitter {
             };
 
             if (cookieStr) requestCtx.headers.cookie = cookieStr;
-
+            requestCtx.headers.Host = requestCtx.url.host;
 
             const reqEvent = new HookEvent(requestCtx, null, null);
             this.emit('request', reqEvent);
@@ -783,4 +783,4 @@ function eventTargetAgnosticAddListener(emitter, name, listener, flags) {
   } else {
     throw new TypeError('The "emitter" argument must be of type EventEmitter. Received type ' + typeof emitter);
   }
-}
\ No newline at end of file
+}