diff --git a/packages/@angular/cli/tasks/test.ts b/packages/@angular/cli/tasks/test.ts
index 76ff6ec7f300..7c038953d00c 100644
--- a/packages/@angular/cli/tasks/test.ts
+++ b/packages/@angular/cli/tasks/test.ts
@@ -31,7 +31,7 @@ export default Task.extend({
 
       karmaOptions.angularCli = {
         codeCoverage: options.codeCoverage,
-        sourcemap: options.sourcemaps,
+        sourcemaps: options.sourcemaps,
         progress: options.progress,
         poll: options.poll,
         app: options.app