Stepping motor is playing an increasingly important role in modern control. In order to guarantee the reliability of the product, the stepping motor’s life becomes especially important. The evaluation system based on Windows can solve the problem very well. However due to the Windows operating system has poor realtime performance, the driving signal timing produced by it can’t meet the requirements of stepping motor which requires precise timing. This paper adopted the hard realtime solution RTX based on Windows which is produced by Ardence. Combining with the experiments of project about stepping motor life, the paper summarized the design method and development process of RTX realtime application system. It is proved by experiments that drive signal generated based on RTX can satisfy the demands of stepping motor. Additionally, it is not affected by the external events and has good repeatability. As a result, the method is realtime, stable and reliable.