diff --git a/packages/core/src/view/ng_module.ts b/packages/core/src/view/ng_module.ts
index 15496ce80f..bd660bf817 100644
--- a/packages/core/src/view/ng_module.ts
+++ b/packages/core/src/view/ng_module.ts
@@ -43,7 +43,7 @@ export function moduleDef(providers: NgModuleProviderDef[]): NgModuleDefinition
   let isRoot: boolean = false;
   for (let i = 0; i < providers.length; i++) {
     const provider = providers[i];
-    if (provider.token === APP_ROOT) {
+    if (provider.token === APP_ROOT && provider.value === true) {
       isRoot = true;
     }
     if (provider.flags & NodeFlags.TypeNgModule) {
diff --git a/packages/core/test/view/ng_module_spec.ts b/packages/core/test/view/ng_module_spec.ts
index 3d569c844b..34ce8fbeb9 100644
--- a/packages/core/test/view/ng_module_spec.ts
+++ b/packages/core/test/view/ng_module_spec.ts
@@ -14,6 +14,7 @@ import {NgModuleDefinition, NgModuleProviderDef, NodeFlags} from '@angular/core/
 import {moduleDef, moduleProvideDef, resolveNgModuleDep} from '@angular/core/src/view/ng_module';
 import {createNgModuleRef} from '@angular/core/src/view/refs';
 import {tokenKey} from '@angular/core/src/view/util';
+import {APP_ROOT} from '../../src/di/scope';
 
 class Foo {}
 
@@ -229,4 +230,29 @@ describe('NgModuleRef_ injector', () => {
     ref.destroy();
     expect(Service.destroyed).toBe(1);
   });
+
+  describe('moduleDef', () => {
+    function createProvider(token: any, value: any) {
+      return {
+        index: 0,
+        flags: NodeFlags.TypeValueProvider | NodeFlags.LazyProvider,
+        deps: [], token, value
+      };
+    }
+
+    it('sets isRoot to `true` when APP_ROOT is `true`', () => {
+      const def = moduleDef([createProvider(APP_ROOT, true)]);
+      expect(def.isRoot).toBe(true);
+    });
+
+    it('sets isRoot to `false` when APP_ROOT is absent', () => {
+      const def = moduleDef([]);
+      expect(def.isRoot).toBe(false);
+    });
+
+    it('sets isRoot to `false` when APP_ROOT is `false`', () => {
+      const def = moduleDef([createProvider(APP_ROOT, false)]);
+      expect(def.isRoot).toBe(false);
+    });
+  });
 });