Abstract: Because four redundancy servo control system is designed by limited life and high reliability, reliability testing base on exponential distribution is difficult to achieve the effect, which need large samples and long testing time. According to the failure mechanism of four redundancy servo control system, this paper studies the reliability testing method, presents a reliability testing and statistical method based on Weibull process. Based on three assumptions, this paper deals with the operational point in the end of life with the linear method. Considering the transient failure rate of Weibull process in little time as the failure rate, this paper contacts the exponential distribution reliability testing method with the Weibull process method. Application of four redundancy servo control stem indicates that the Weibull process reliability testing method can reduce the testing time and samples, and it provides an effective method to high reliability mechatronic products.