Abstract: Nowadays software applications are increasingly becoming large in scale and complexity, thus, Graphical User Interface (GUI) testing plays a formal important role in ensuring the correctness and reliability of software applications. A variety of approaches in the area of GUI testing have emerged in recent years. One notable trend is Model-Based Testing (MBT) which creates an abstract test model that simulates the anticipated behavior of the System Under Testing (SUT) by using some software generated tools to generate model tests. This study highlights the designing as well as the presentation of a new automation testing framework for silverlight applications with particular focuses upon the integration of the Spec Explorer based MBT with a free web framework called WebAii. Both of the tools are available as open source. Spec Explorer can be used to generate the test cases automatically, while WebAii is used to simulate human action and operation processes to complete the test execution in an automated way.