--- a/dom/bindings/BindingUtils.cpp
+++ b/dom/bindings/BindingUtils.cpp
@@ -2941,17 +2941,18 @@ IsNonExposedGlobal(JSContext* aCx, JSObj
   MOZ_ASSERT(aNonExposedGlobals, "Why did we get called?");
   MOZ_ASSERT((aNonExposedGlobals &
               ~(GlobalNames::Window |
                 GlobalNames::BackstagePass |
                 GlobalNames::DedicatedWorkerGlobalScope |
                 GlobalNames::SharedWorkerGlobalScope |
                 GlobalNames::ServiceWorkerGlobalScope |
                 GlobalNames::WorkerDebuggerGlobalScope |
-                GlobalNames::WorkletGlobalScope)) == 0,
+                GlobalNames::WorkletGlobalScope |
+                GlobalNames::AudioWorkletGlobalScope)) == 0,
              "Unknown non-exposed global type");
 
   const char* name = js::GetObjectClass(aGlobal)->name;
 
   if ((aNonExposedGlobals & GlobalNames::Window) &&
       !strcmp(name, "Window")) {
     return true;
   }
@@ -2981,16 +2982,21 @@ IsNonExposedGlobal(JSContext* aCx, JSObj
     return true;
   }
 
   if ((aNonExposedGlobals & GlobalNames::WorkletGlobalScope) &&
       !strcmp(name, "WorkletGlobalScope")) {
     return true;
   }
 
+  if ((aNonExposedGlobals & GlobalNames::AudioWorkletGlobalScope) &&
+      !strcmp(name, "AudioWorkletGlobalScope")) {
+    return true;
+  }
+
   return false;
 }
 
 namespace binding_detail {
 
 /**
  * A ThisPolicy struct needs to provide the following methods:
  *

--- a/dom/bindings/DOMJSClass.h
+++ b/dom/bindings/DOMJSClass.h
@@ -101,16 +101,17 @@ namespace GlobalNames {
 // annotations.
 static const uint32_t Window = 1u << 0;
 static const uint32_t BackstagePass = 1u << 1;
 static const uint32_t DedicatedWorkerGlobalScope = 1u << 2;
 static const uint32_t SharedWorkerGlobalScope = 1u << 3;
 static const uint32_t ServiceWorkerGlobalScope = 1u << 4;
 static const uint32_t WorkerDebuggerGlobalScope = 1u << 5;
 static const uint32_t WorkletGlobalScope = 1u << 6;
+static const uint32_t AudioWorkletGlobalScope = 1u << 7;
 } // namespace GlobalNames
 
 struct PrefableDisablers {
   inline bool isEnabled(JSContext* cx, JS::Handle<JSObject*> obj) const {
     // Reading "enabled" on a worker thread is technically undefined behavior,
     // because it's written only on main threads, with no barriers of any sort.
     // So we want to avoid doing that.  But we don't particularly want to make
     // expensive NS_IsMainThread calls here.

new file mode 100644
--- /dev/null
+++ b/dom/media/webaudio/AudioWorkletProcessor.cpp
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "AudioWorkletProcessor.h"
+
+#include "mozilla/dom/AudioWorkletNodeBinding.h"
+#include "mozilla/dom/AudioWorkletProcessorBinding.h"
+#include "mozilla/dom/MessagePort.h"
+#include "nsIGlobalObject.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(AudioWorkletProcessor, mParent)
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(AudioWorkletProcessor, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(AudioWorkletProcessor, Release)
+
+AudioWorkletProcessor::AudioWorkletProcessor(nsIGlobalObject* aParent)
+  : mParent(aParent)
+{
+}
+
+/* static */ already_AddRefed<AudioWorkletProcessor>
+AudioWorkletProcessor::Constructor(const GlobalObject& aGlobal,
+                                   const AudioWorkletNodeOptions& aOptions,
+                                   ErrorResult& aRv)
+{
+  nsCOMPtr<nsIGlobalObject> global =
+      do_QueryInterface(aGlobal.GetAsSupports());
+  MOZ_ASSERT(global);
+
+  RefPtr<AudioWorkletProcessor> audioWorkletProcessor =
+      new AudioWorkletProcessor(global);
+
+  return audioWorkletProcessor.forget();
+}
+
+JSObject*
+AudioWorkletProcessor::WrapObject(JSContext* aCx,
+                                  JS::Handle<JSObject*> aGivenProto)
+{
+  return AudioWorkletProcessor_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+MessagePort*
+AudioWorkletProcessor::GetPort(ErrorResult& aRv) const
+{
+  aRv.Throw(NS_ERROR_NOT_IMPLEMENTED);
+  return nullptr;
+}
+
+} // namespace dom
+} // namespace mozilla

new file mode 100644
--- /dev/null
+++ b/dom/media/webaudio/AudioWorkletProcessor.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#ifndef AudioWorkletProcessor_h_
+#define AudioWorkletProcessor_h_
+
+#include "nsCOMPtr.h"
+#include "nsWrapperCache.h"
+
+struct AudioWorkletNodeOptions;
+class ErrorResult;
+class GlobalObject;
+class MessagePort;
+class nsIGlobalObject;
+
+namespace mozilla {
+namespace dom {
+
+class AudioWorkletProcessor final : public nsWrapperCache
+{
+public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AudioWorkletProcessor)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(AudioWorkletProcessor)
+
+  static already_AddRefed<AudioWorkletProcessor>
+  Constructor(const GlobalObject& aGlobal,
+              const AudioWorkletNodeOptions& aOptions,
+              ErrorResult& aRv);
+
+  nsIGlobalObject* GetParentObject() const { return mParent; }
+
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  MessagePort* GetPort(ErrorResult& aRv) const;
+
+private:
+  explicit AudioWorkletProcessor(nsIGlobalObject* aParent);
+  ~AudioWorkletProcessor() = default;
+  nsCOMPtr<nsIGlobalObject> mParent;
+};
+
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // AudioWorkletProcessor_h_

--- a/dom/media/webaudio/moz.build
+++ b/dom/media/webaudio/moz.build
@@ -48,16 +48,17 @@ EXPORTS.mozilla.dom += [
     'AudioDestinationNode.h',
     'AudioListener.h',
     'AudioNode.h',
     'AudioParam.h',
     'AudioParamMap.h',
     'AudioProcessingEvent.h',
     'AudioScheduledSourceNode.h',
     'AudioWorkletNode.h',
+    'AudioWorkletProcessor.h',
     'BiquadFilterNode.h',
     'ChannelMergerNode.h',
     'ChannelSplitterNode.h',
     'ConstantSourceNode.h',
     'ConvolverNode.h',
     'DelayNode.h',
     'DynamicsCompressorNode.h',
     'GainNode.h',
@@ -86,16 +87,17 @@ UNIFIED_SOURCES += [
     'AudioNodeEngine.cpp',
     'AudioNodeExternalInputStream.cpp',
     'AudioNodeStream.cpp',
     'AudioParam.cpp',
     'AudioParamMap.cpp',
     'AudioProcessingEvent.cpp',
     'AudioScheduledSourceNode.cpp',
     'AudioWorkletNode.cpp',
+    'AudioWorkletProcessor.cpp',
     'BiquadFilterNode.cpp',
     'ChannelMergerNode.cpp',
     'ChannelSplitterNode.cpp',
     'ConstantSourceNode.cpp',
     'ConvolverNode.cpp',
     'DelayBuffer.cpp',
     'DelayNode.cpp',
     'DynamicsCompressorNode.cpp',

new file mode 100644
--- /dev/null
+++ b/dom/webidl/AudioWorkletProcessor.webidl
@@ -0,0 +1,18 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/.
+ *
+ * The origin of this IDL file is
+ * https://webaudio.github.io/web-audio-api/#audioworkletprocessor
+ *
+ * Copyright © 2018 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C
+ * liability, trademark and document use rules apply.
+ */
+
+[Exposed=AudioWorklet,
+ Constructor (optional AudioWorkletNodeOptions options)]
+interface AudioWorkletProcessor {
+    [Throws]
+    readonly attribute MessagePort port;
+};

--- a/dom/webidl/EventTarget.webidl
+++ b/dom/webidl/EventTarget.webidl
@@ -19,17 +19,17 @@ dictionary EventListenerOptions {
 };
 
 dictionary AddEventListenerOptions : EventListenerOptions {
   boolean passive;
   boolean once = false;
 };
 
 [Constructor,
- Exposed=(Window,Worker,WorkerDebugger,System)]
+ Exposed=(Window,Worker,WorkerDebugger,AudioWorklet,System)]
 interface EventTarget {
   /* Passing null for wantsUntrusted means "default behavior", which
      differs in content and chrome.  In content that default boolean
      value is true, while in chrome the default boolean value is
      false. */
   [Throws]
   void addEventListener(DOMString type,
                         EventListener? listener,

--- a/dom/webidl/MessagePort.webidl
+++ b/dom/webidl/MessagePort.webidl
@@ -2,17 +2,17 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * 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/.
  *
  * For more information on this interface, please see
  * http://www.whatwg.org/specs/web-apps/current-work/#channel-messaging
  */
 
-[Exposed=(Window,Worker,System)]
+[Exposed=(Window,Worker,AudioWorklet,System)]
 interface MessagePort : EventTarget {
   [Throws]
   void postMessage(any message, optional sequence<object> transferable = []);
 
   void start();
   void close();
 
   // event handlers

--- a/dom/webidl/moz.build
+++ b/dom/webidl/moz.build
@@ -381,16 +381,17 @@ WEBIDL_FILES = [
     'AudioParamMap.webidl',
     'AudioProcessingEvent.webidl',
     'AudioScheduledSourceNode.webidl',
     'AudioStreamTrack.webidl',
     'AudioTrack.webidl',
     'AudioTrackList.webidl',
     'AudioWorkletGlobalScope.webidl',
     'AudioWorkletNode.webidl',
+    'AudioWorkletProcessor.webidl',
     'AutocompleteInfo.webidl',
     'BarProp.webidl',
     'BaseAudioContext.webidl',
     'BaseKeyframeTypes.webidl',
     'BasicCardPayment.webidl',
     'BatteryManager.webidl',
     'BeforeUnloadEvent.webidl',
     'BiquadFilterNode.webidl',