diff --git a/packages/@ember/-internals/metal/index.ts b/packages/@ember/-internals/metal/index.ts
index 357244e49f2..a5cc6f31277 100644
--- a/packages/@ember/-internals/metal/index.ts
+++ b/packages/@ember/-internals/metal/index.ts
@@ -29,11 +29,11 @@ export {
   PROPERTY_DID_CHANGE,
 } from './lib/property_events';
 export { defineProperty } from './lib/properties';
-export { nativeDescDecorator } from './lib/decorator';
+export { isElementDescriptor, nativeDescDecorator } from './lib/decorator';
 export {
   descriptorForProperty,
-  isComputedDecorator,
-  setComputedDecorator,
+  isClassicDecorator,
+  setClassicDecorator,
 } from './lib/descriptor_map';
 export { watchKey, unwatchKey } from './lib/watch_key';
 export { ChainNode, finishChains, removeChainWatcher } from './lib/chains';
diff --git a/packages/@ember/-internals/metal/lib/computed.ts b/packages/@ember/-internals/metal/lib/computed.ts
index 750c45d57c3..b705fea6404 100644
--- a/packages/@ember/-internals/metal/lib/computed.ts
+++ b/packages/@ember/-internals/metal/lib/computed.ts
@@ -22,7 +22,7 @@ import {
   makeComputedDecorator,
   removeDependentKeys,
 } from './decorator';
-import { descriptorForDecorator, isComputedDecorator } from './descriptor_map';
+import { descriptorForDecorator, isClassicDecorator } from './descriptor_map';
 import expandProperties from './expand_properties';
 import { defineProperty } from './properties';
 import { notifyPropertyChange } from './property_events';
@@ -180,7 +180,7 @@ export class ComputedProperty extends ComputedDescriptor {
       if (typeof config === 'function') {
         assert(
           `You attempted to pass a computed property instance to computed(). Computed property instances are decorator functions, and cannot be passed to computed() because they cannot be turned into decorators twice`,
-          !isComputedDecorator(config)
+          !isClassicDecorator(config)
         );
 
         this._getter = config as ComputedPropertyGetter;
diff --git a/packages/@ember/-internals/metal/lib/decorator.ts b/packages/@ember/-internals/metal/lib/decorator.ts
index b0489fa1947..8b5d3513b6a 100644
--- a/packages/@ember/-internals/metal/lib/decorator.ts
+++ b/packages/@ember/-internals/metal/lib/decorator.ts
@@ -1,7 +1,7 @@
 import { Meta, meta as metaFor } from '@ember/-internals/meta';
 import { EMBER_NATIVE_DECORATOR_SUPPORT } from '@ember/canary-features';
 import { assert } from '@ember/debug';
-import { setComputedDecorator } from './descriptor_map';
+import { setClassicDecorator } from './descriptor_map';
 import { unwatch, watch } from './watching';
 
 export type DecoratorPropertyDescriptor = PropertyDescriptor & { initializer?: any } | undefined;
@@ -90,7 +90,7 @@ export function nativeDescDecorator(propertyDesc: PropertyDescriptor) {
     return propertyDesc;
   };
 
-  setComputedDecorator(decorator);
+  setClassicDecorator(decorator);
 
   return decorator;
 }
@@ -170,7 +170,7 @@ export function makeComputedDecorator(
     };
   };
 
-  setComputedDecorator(decorator, desc);
+  setClassicDecorator(decorator, desc);
 
   Object.setPrototypeOf(decorator, DecoratorClass.prototype);
 
diff --git a/packages/@ember/-internals/metal/lib/descriptor_map.ts b/packages/@ember/-internals/metal/lib/descriptor_map.ts
index b228e0646a6..dcc5fd5796e 100644
--- a/packages/@ember/-internals/metal/lib/descriptor_map.ts
+++ b/packages/@ember/-internals/metal/lib/descriptor_map.ts
@@ -37,22 +37,22 @@ export function descriptorForDecorator(dec: import('./decorator').Decorator) {
 /**
   Check whether a value is a decorator
 
-  @method isComputedDecorator
+  @method isClassicDecorator
   @param {any} possibleDesc the value to check
   @return {boolean}
   @private
 */
-export function isComputedDecorator(dec: any) {
+export function isClassicDecorator(dec: any) {
   return dec !== null && dec !== undefined && DECORATOR_DESCRIPTOR_MAP.has(dec);
 }
 
 /**
   Set a value as a decorator
 
-  @method setComputedDecorator
+  @method setClassicDecorator
   @param {function} decorator the value to mark as a decorator
   @private
 */
-export function setComputedDecorator(dec: import('./decorator').Decorator, value: any = true) {
+export function setClassicDecorator(dec: import('./decorator').Decorator, value: any = true) {
   DECORATOR_DESCRIPTOR_MAP.set(dec, value);
 }
diff --git a/packages/@ember/-internals/metal/lib/mixin.ts b/packages/@ember/-internals/metal/lib/mixin.ts
index d59c74865e3..4c3e25d59af 100644
--- a/packages/@ember/-internals/metal/lib/mixin.ts
+++ b/packages/@ember/-internals/metal/lib/mixin.ts
@@ -27,7 +27,7 @@ import { makeComputedDecorator, nativeDescDecorator } from './decorator';
 import {
   descriptorForDecorator,
   descriptorForProperty,
-  isComputedDecorator,
+  isClassicDecorator,
 } from './descriptor_map';
 import { addListener, removeListener } from './events';
 import expandProperties from './expand_properties';
@@ -277,7 +277,7 @@ function addNormalizedProperty(
   concats?: string[],
   mergings?: string[]
 ): void {
-  if (isComputedDecorator(value)) {
+  if (isClassicDecorator(value)) {
     // Wrap descriptor function to implement _super() if needed
     descs[key] = giveDecoratorSuper(meta, key, value, values, descs, base);
     values[key] = undefined;
diff --git a/packages/@ember/-internals/metal/lib/properties.ts b/packages/@ember/-internals/metal/lib/properties.ts
index 35689551441..0c468490a6f 100644
--- a/packages/@ember/-internals/metal/lib/properties.ts
+++ b/packages/@ember/-internals/metal/lib/properties.ts
@@ -6,7 +6,7 @@ import { Meta, meta as metaFor, peekMeta, UNDEFINED } from '@ember/-internals/me
 import { assert } from '@ember/debug';
 import { DEBUG } from '@glimmer/env';
 import { Decorator } from './decorator';
-import { descriptorForProperty, isComputedDecorator } from './descriptor_map';
+import { descriptorForProperty, isClassicDecorator } from './descriptor_map';
 import { overrideChains } from './property_events';
 
 export type MandatorySetterFunction = ((this: object, value: any) => void) & {
@@ -149,7 +149,7 @@ export function defineProperty(
   }
 
   let value;
-  if (isComputedDecorator(desc)) {
+  if (isClassicDecorator(desc)) {
     let propertyDesc;
 
     if (DEBUG) {
diff --git a/packages/@ember/-internals/metal/lib/tracked.ts b/packages/@ember/-internals/metal/lib/tracked.ts
index 8b0e9feeef7..75abe6c3768 100644
--- a/packages/@ember/-internals/metal/lib/tracked.ts
+++ b/packages/@ember/-internals/metal/lib/tracked.ts
@@ -4,7 +4,7 @@ import { assert } from '@ember/debug';
 import { DEBUG } from '@glimmer/env';
 import { combine, CONSTANT_TAG, Tag } from '@glimmer/reference';
 import { Decorator, DecoratorPropertyDescriptor, isElementDescriptor } from './decorator';
-import { setComputedDecorator } from './descriptor_map';
+import { setClassicDecorator } from './descriptor_map';
 import { dirty, ensureRunloop, tagFor, tagForProperty } from './tags';
 
 type Option<T> = T | null;
@@ -164,7 +164,7 @@ export function tracked(...args: any[]): Decorator | DecoratorPropertyDescriptor
       return descriptorForField([target, key, fieldDesc]);
     };
 
-    setComputedDecorator(decorator);
+    setClassicDecorator(decorator);
 
     return decorator;
   }
@@ -180,7 +180,7 @@ export function tracked(...args: any[]): Decorator | DecoratorPropertyDescriptor
 if (DEBUG) {
   // Normally this isn't a classic decorator, but we want to throw a helpful
   // error in development so we need it to treat it like one
-  setComputedDecorator(tracked);
+  setClassicDecorator(tracked);
 }
 
 function descriptorForField([_target, key, desc]: [
diff --git a/packages/@ember/-internals/metal/lib/watch_key.ts b/packages/@ember/-internals/metal/lib/watch_key.ts
index 062681e9c99..d087258bf27 100644
--- a/packages/@ember/-internals/metal/lib/watch_key.ts
+++ b/packages/@ember/-internals/metal/lib/watch_key.ts
@@ -1,7 +1,7 @@
 import { Meta, meta as metaFor, peekMeta, UNDEFINED } from '@ember/-internals/meta';
 import { lookupDescriptor } from '@ember/-internals/utils';
 import { DEBUG } from '@glimmer/env';
-import { descriptorForProperty, isComputedDecorator } from './descriptor_map';
+import { descriptorForProperty, isClassicDecorator } from './descriptor_map';
 import {
   DEFAULT_GETTER_FUNCTION,
   INHERITING_GETTER_FUNCTION,
@@ -56,7 +56,7 @@ if (DEBUG) {
     let descriptor = lookupDescriptor(obj, keyName);
     let hasDescriptor = descriptor !== null;
     let possibleDesc = hasDescriptor && descriptor!.value;
-    if (isComputedDecorator(possibleDesc)) {
+    if (isClassicDecorator(possibleDesc)) {
       return;
     }
     let configurable = hasDescriptor ? descriptor!.configurable : true;
diff --git a/packages/@ember/-internals/metal/tests/computed_test.js b/packages/@ember/-internals/metal/tests/computed_test.js
index 52e3df08718..4027c8136a7 100644
--- a/packages/@ember/-internals/metal/tests/computed_test.js
+++ b/packages/@ember/-internals/metal/tests/computed_test.js
@@ -3,7 +3,7 @@ import {
   computed,
   getCachedValueFor,
   defineProperty,
-  isComputedDecorator,
+  isClassicDecorator,
   get,
   set,
   isWatching,
@@ -18,7 +18,7 @@ moduleFor(
   'computed',
   class extends AbstractTestCase {
     ['@test computed property should be an instance of descriptor'](assert) {
-      assert.ok(isComputedDecorator(computed(function() {})));
+      assert.ok(isClassicDecorator(computed(function() {})));
     }
 
     ['@test computed properties assert the presence of a getter or setter function']() {
diff --git a/packages/@ember/-internals/metal/tests/injected_property_test.js b/packages/@ember/-internals/metal/tests/injected_property_test.js
index 06434e74920..734ce2ed2cb 100644
--- a/packages/@ember/-internals/metal/tests/injected_property_test.js
+++ b/packages/@ember/-internals/metal/tests/injected_property_test.js
@@ -1,12 +1,12 @@
 import { setOwner } from '@ember/-internals/owner';
-import { defineProperty, get, isComputedDecorator, set, inject } from '..';
+import { defineProperty, get, isClassicDecorator, set, inject } from '..';
 import { moduleFor, AbstractTestCase } from 'internal-test-helpers';
 
 moduleFor(
   'inject',
   class extends AbstractTestCase {
     ['@test injected properties should be descriptors'](assert) {
-      assert.ok(isComputedDecorator(inject('type')));
+      assert.ok(isClassicDecorator(inject('type')));
     }
 
     ['@test injected properties should be overridable'](assert) {
diff --git a/packages/@ember/-internals/runtime/lib/system/core_object.js b/packages/@ember/-internals/runtime/lib/system/core_object.js
index 87bc7487303..9c220cc6299 100644
--- a/packages/@ember/-internals/runtime/lib/system/core_object.js
+++ b/packages/@ember/-internals/runtime/lib/system/core_object.js
@@ -23,7 +23,7 @@ import {
   defineProperty,
   descriptorForProperty,
   classToString,
-  isComputedDecorator,
+  isClassicDecorator,
   DEBUG_INJECTION_FUNCTIONS,
 } from '@ember/-internals/metal';
 import ActionHandler from '../mixins/action_handler';
@@ -78,7 +78,7 @@ function initialize(obj, properties) {
         'EmberObject.create no longer supports defining computed ' +
           'properties. Define computed properties using extend() or reopen() ' +
           'before calling create().',
-        !isComputedDecorator(value)
+        !isClassicDecorator(value)
       );
       assert(
         'EmberObject.create no longer supports defining methods that call _super.',
diff --git a/packages/@ember/object/index.js b/packages/@ember/object/index.js
index e28e8c452aa..cc02ee6567f 100644
--- a/packages/@ember/object/index.js
+++ b/packages/@ember/object/index.js
@@ -1,6 +1,7 @@
 import { EMBER_NATIVE_DECORATOR_SUPPORT } from '@ember/canary-features';
 import { assert } from '@ember/debug';
 import { assign } from '@ember/polyfills';
+import { isElementDescriptor, setClassicDecorator } from '@ember/-internals/metal';
 
 /**
   Decorator that turns the target function into an Action
@@ -41,11 +42,7 @@ export let action;
 if (EMBER_NATIVE_DECORATOR_SUPPORT) {
   let BINDINGS_MAP = new WeakMap();
 
-  action = function action(target, key, desc) {
-    assert('The @action decorator must be applied to methods', typeof desc.value === 'function');
-
-    let actionFn = desc.value;
-
+  let setupAction = function(target, key, actionFn) {
     if (target.constructor !== undefined && typeof target.constructor.proto === 'function') {
       target.constructor.proto();
     }
@@ -78,4 +75,41 @@ if (EMBER_NATIVE_DECORATOR_SUPPORT) {
       },
     };
   };
+
+  action = function action(target, key, desc) {
+    let actionFn;
+
+    if (!isElementDescriptor([target, key, desc])) {
+      actionFn = target;
+
+      let decorator = function(target, key, desc, meta, isClassicDecorator) {
+        assert(
+          'The @action decorator may only be passed a method when used in classic classes. You should decorate methods directly in native classes',
+          isClassicDecorator
+        );
+
+        assert(
+          'The action() decorator must be passed a method when used in classic classes',
+          typeof actionFn === 'function'
+        );
+
+        return setupAction(target, key, actionFn);
+      };
+
+      setClassicDecorator(decorator);
+
+      return decorator;
+    }
+
+    actionFn = desc.value;
+
+    assert(
+      'The @action decorator must be applied to methods when used in native classes',
+      typeof actionFn === 'function'
+    );
+
+    return setupAction(target, key, actionFn);
+  };
+
+  setClassicDecorator(action);
 }
diff --git a/packages/@ember/object/tests/action_test.js b/packages/@ember/object/tests/action_test.js
index 23dfc317b27..d1ccc8c0bcb 100644
--- a/packages/@ember/object/tests/action_test.js
+++ b/packages/@ember/object/tests/action_test.js
@@ -231,6 +231,50 @@ if (EMBER_NATIVE_DECORATOR_SUPPORT) {
           new TestObject();
         }, /The @action decorator must be applied to methods/);
       }
+
+      '@test action decorator throws an error if passed a function in native classes'() {
+        expectAssertion(() => {
+          class TestObject extends EmberObject {
+            @action(function() {}) foo = 'bar';
+          }
+
+          new TestObject();
+        }, /The @action decorator may only be passed a method when used in classic classes/);
+      }
+
+      '@test action decorator can be used as a classic decorator with strings'(assert) {
+        let FooComponent = Component.extend({
+          foo: action(function() {
+            assert.ok(true, 'called!');
+          }),
+        });
+
+        this.registerComponent('foo-bar', {
+          ComponentClass: FooComponent,
+          template: "<button {{action 'foo'}}>Click Me!</button>",
+        });
+
+        this.render('{{foo-bar}}');
+
+        this.$('button').click();
+      }
+
+      '@test action decorator can be used as a classic decorator directly'(assert) {
+        let FooComponent = Component.extend({
+          foo: action(function() {
+            assert.ok(true, 'called!');
+          }),
+        });
+
+        this.registerComponent('foo-bar', {
+          ComponentClass: FooComponent,
+          template: '<button onclick={{this.foo}}>Click Me!</button>',
+        });
+
+        this.render('{{foo-bar}}');
+
+        this.$('button').click();
+      }
     }
   );
 }
diff --git a/packages/ember/index.js b/packages/ember/index.js
index fdda6f97ecc..8c415902eaa 100644
--- a/packages/ember/index.js
+++ b/packages/ember/index.js
@@ -275,7 +275,7 @@ Ember._tracked = metal.tracked;
 computed.alias = metal.alias;
 Ember.cacheFor = metal.getCachedValueFor;
 Ember.ComputedProperty = metal.ComputedProperty;
-Ember._setComputedDecorator = metal.setComputedDecorator;
+Ember._setClassicDecorator = metal.setClassicDecorator;
 Ember.meta = meta;
 Ember.get = metal.get;
 Ember.getWithDefault = metal.getWithDefault;
diff --git a/packages/ember/tests/reexports_test.js b/packages/ember/tests/reexports_test.js
index 62d310aa4be..a3ada5b56c3 100644
--- a/packages/ember/tests/reexports_test.js
+++ b/packages/ember/tests/reexports_test.js
@@ -113,7 +113,7 @@ let allExports = [
   ['_tracked', '@ember/-internals/metal', 'tracked'],
   ['computed.alias', '@ember/-internals/metal', 'alias'],
   ['ComputedProperty', '@ember/-internals/metal'],
-  ['_setComputedDecorator', '@ember/-internals/metal', 'setComputedDecorator'],
+  ['_setClassicDecorator', '@ember/-internals/metal', 'setClassicDecorator'],
   ['cacheFor', '@ember/-internals/metal', 'getCachedValueFor'],
   ['merge', '@ember/polyfills'],
   ['instrument', '@ember/instrumentation'],
diff --git a/tests/docs/expected.js b/tests/docs/expected.js
index 72ceeb1822d..58d6371f883 100644
--- a/tests/docs/expected.js
+++ b/tests/docs/expected.js
@@ -298,7 +298,7 @@ module.exports = {
     'isArray',
     'isBlank',
     'isBrowser',
-    'isComputedDecorator',
+    'isClassicDecorator',
     'isDestroyed',
     'isDestroying',
     'isEmpty',
@@ -501,7 +501,7 @@ module.exports = {
     'serializeQueryParam',
     'serializeQueryParamKey',
     'set',
-    'setComputedDecorator',
+    'setClassicDecorator',
     'setDiff',
     'setEach',
     'setEngineParent',