A new method is proposed to develop a test system about a kind of automatic pilot. With the help of Real-Time Windows Target Toolbox in MATLAB. operating on PC cards is very simple. Using the components like data acquisition cards basing on SimuLink Toolbox of MATLAB,a real-time simulink model can be built easily. A graphic user interface is developed with the GUI tool in MAT-LAB. When developing a test system, in addition to using the advantage in computing and displaying of MATLAB, operating on hardware is also supported. The final result validates the feasibility and facility of this method.