diff --git a/packages/ember-data/lib/serializers/rest-serializer.js b/packages/ember-data/lib/serializers/rest-serializer.js
index 768bdcd1f8e..a987ffa6202 100644
--- a/packages/ember-data/lib/serializers/rest-serializer.js
+++ b/packages/ember-data/lib/serializers/rest-serializer.js
@@ -145,10 +145,19 @@ var RESTSerializer = JSONSerializer.extend({
       included: []
     };
 
-    let modelClass = store.modelFor(modelName);
-    let serializer = store.serializerFor(modelName);
+    let primaryModelClass = store.modelFor(modelName);
+    let primarySerializer = store.serializerFor(modelName);
 
     arrayHash.forEach((hash) => {
+      let serializer, modelClass;
+      // Support polymorphic records in async relationships
+      if (hash.type && store._hasModelFor(this.modelNameFromPayloadKey(hash.type))) {
+        serializer = store.serializerFor(hash.type);
+        modelClass = store.modelFor(hash.type);
+      } else {
+        serializer = primarySerializer;
+        modelClass = primaryModelClass;
+      }
       let { data, included } = serializer.normalize(modelClass, hash, prop);
       documentHash.data.push(data);
       if (included) {
@@ -239,7 +248,16 @@ var RESTSerializer = JSONSerializer.extend({
         ```
        */
       if (isPrimary && Ember.typeOf(value) !== 'array') {
-        let {data, included} = this.normalize(primaryModelClass, value, prop);
+        var serializer, modelClass;
+        // Support polymorphic records in async relationships
+        if (value.type && store._hasModelFor(this.modelNameFromPayloadKey(value.type))) {
+          serializer = store.serializerFor(value.type);
+          modelClass = store.modelFor(value.type);
+        } else {
+          serializer = this;
+          modelClass = primaryModelClass;
+        }
+        let {data, included} = serializer.normalize(modelClass, value, prop);
         documentHash.data = data;
         if (included) {
           documentHash.included.push(...included);
diff --git a/packages/ember-data/tests/integration/serializers/rest-serializer-test.js b/packages/ember-data/tests/integration/serializers/rest-serializer-test.js
index fd1b6fec768..30ffa0f7383 100644
--- a/packages/ember-data/tests/integration/serializers/rest-serializer-test.js
+++ b/packages/ember-data/tests/integration/serializers/rest-serializer-test.js
@@ -17,7 +17,9 @@ module("integration/serializer/rest - RESTSerializer", {
       superVillain: DS.belongsTo('super-villain', { async: false }),
       name:         DS.attr('string')
     });
-    YellowMinion = EvilMinion.extend();
+    YellowMinion = EvilMinion.extend({
+      eyes: DS.attr('number')
+    });
     DoomsdayDevice = DS.Model.extend({
       name:         DS.attr('string'),
       evilMinion:   DS.belongsTo('evil-minion', { polymorphic: true, async: true })
@@ -461,6 +463,81 @@ test('serializeIntoHash uses payloadKeyFromModelName to normalize the payload ro
   });
 });
 
+test('normalizeResponse with async polymorphic belongsTo', function() {
+  env.registry.register('serializer:application', DS.RESTSerializer.extend({
+    isNewSerializerAPI: true
+  }));
+  var store = env.store;
+  env.adapter.findRecord = () => {
+    return {
+      doomsdayDevices: [{
+        id: 1,
+        name: "DeathRay",
+        links: {
+          evilMinion: '/doomsday-device/1/evil-minion'
+        }
+      }]
+    };
+  };
+
+  env.adapter.findBelongsTo = () => {
+    return {
+      evilMinion: {
+        id: 1,
+        type: 'yellowMinion',
+        name: 'Alex',
+        eyes: 3
+      }
+    };
+  };
+  run(function() {
+    store.findRecord('doomsday-device', 1).then((deathRay) => {
+      return deathRay.get('evilMinion');
+    }).then((evilMinion) => {
+      equal(evilMinion.get('eyes'), 3);
+    });
+  });
+});
+
+test('normalizeResponse with async polymorphic hasMany', function() {
+  SuperVillain.reopen({ evilMinions: DS.hasMany('evil-minion', { async: true, polymorphic: true }) });
+  env.registry.register('serializer:application', DS.RESTSerializer.extend({
+    isNewSerializerAPI: true
+  }));
+  var store = env.store;
+  env.adapter.findRecord = () => {
+    return {
+      superVillains: [{
+        id: "1",
+        firstName: "Yehuda",
+        lastName: "Katz",
+        links: {
+          evilMinions: '/super-villain/1/evil-minions'
+        }
+      }]
+    };
+  };
+
+  env.adapter.findHasMany = () => {
+    return {
+      evilMinion: [{
+        id: 1,
+        type: 'yellowMinion',
+        name: 'Alex',
+        eyes: 3
+      }]
+    };
+  };
+  run(function() {
+    store.findRecord('super-villain', 1).then((superVillain) => {
+      return superVillain.get('evilMinions');
+    }).then((evilMinions) => {
+      ok(evilMinions.get('firstObject') instanceof YellowMinion);
+      equal(evilMinions.get('firstObject.eyes'), 3);
+    });
+  });
+});
+
 test("normalizeResponse can load secondary records of the same type without affecting the query count", function() {
   var jsonHash = {
     comments: [{ id: "1", body: "Parent Comment", root: true, children: [2, 3] }],