For wire electrical discharge machining (WEDM) process, the ignition delay time (Td) is a machining parameter often used in the machining performance evaluating. Traditionally, a certain threshold would be set up for the Td so as to divide the electrical discharges into two groups – i.e. when Td is shorter than the threshold, the corresponding electrical discharge would be considered an “abnormal” discharge; otherwise it would be put into the category of “normal” discharges. However, since the physical nature of the electrical discharges in the WEDM process is a stochastic process, the statistical distribution of Td should convey more information regarding the machining performance. With this underlying concept, a low-cost system for monitoring the statistical distribution of Td is proposed and developed in this study. The system is composed of a high-speed microcontroller for data processing and a graphic LCD panel for displaying the statistical distribution of Td on a real-time basis. This system provides the WEDM machine user with an instant graphic of Td distribution. Since graphic information is more intuitive than numerical data to human being, the WEDM user could have a more comprehensive understanding of the working condition. Furthermore, since there would be a certain “ideal Td distribution” corresponding to the optimal machining condition, the WEDM can easily obtain the optimal machining performance by simply making the Td distribution fit to the “ideal distribution” through adjusting the setting of machining parameters. If this scenario could be realized, the WEDM machine would become much easier to operate, which means the learning curve of the WEDM operator would be greatly shorten and the training cost would be less. This study is a pilot exploration. The developed Td distribution monitoring system has demonstrated the feasibility of such an innovated idea in the machining control of WEDM – reaching optimal machining performance by graphic fitting. In this study, experiments under various machining settings have shown that the developed system works satisfactorily. The automatic controlling system for WEDM machine based on this “graphic-oriented” idea would be the focus for following researches.