Wire electrical discharge machining (WEDM) is a well-established non-conventional material removal process capable of meeting the diverse machining requirements posed by the demanding metal cutting industries. It has been commonly applied for the machining and micro-machining of parts with intricate shapes and varying hardness requiring high profile accuracy and tight dimensional tolerances. But WEDM is a complex machining process controlled by a large number of process parameters such as the pulse duration, discharge frequency, discharge current intensity and wire feed rate. Many authors found that when they machined a workpiece with varying thickness, they couldn’t get a good machining performance although they had set suitable process parameters, because it usually happen wire breakage at the processing. So in recent years, the WEDM’s research and development has explored control strategies of adjusting the variation, such as the power density, gap voltage as machining a workpiece with different thickness. Several authors developed their control system to predict and monitor the cutting process. Although these methods increase the level of machine autonomy, they require a large amount of computation, which slows down the processing speed and undermines the online control performance. Hence this paper developed a new system using Pro/toolkit and Visual C++ based on Wildfire Pro/E 3.0 platform. The system can help operator identify the workpiece with varying thickness or through-hole, change process parameters with the varying thickness automatically and generate G-code transfer to the NC machine finally.