diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 7ba8319e4ca..9bd2e622ad7 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -479,7 +479,6 @@ module ActionController
         @request.session["flash"].sweep
 
         @controller.request = @request
-        @controller.params.merge!(parameters)
         build_request_uri(action, parameters)
         @controller.class.class_eval { include Testing }
         @controller.recycle!