diff --git a/modules/angular2/angular2_sfx.ts b/modules/angular2/angular2_sfx.ts
index edd420b58c..150204d0d4 100644
--- a/modules/angular2/angular2_sfx.ts
+++ b/modules/angular2/angular2_sfx.ts
@@ -1,6 +1,6 @@
 import * as ng from './angular2';
 // the router should have its own SFX bundle
-// But currently the module arithemtic 'angular2/router_sfx - angular2/angular2',
+// But currently the module arithmetic 'angular2/router_sfx - angular2/angular2',
 // is not support by system builder.
 import * as router from './router';