The hydraulic system of a pusher drive system was designed based on the analysis of the related materials, and its work principle was introduced, and the parameters of important components in the hydraulic system were calculated. Based on the basic failure probability of the hydraulic element, the reliability mathematical model of the hydraulic system was established by using the reliability calculation method of the series system, and the simulation analysis was carried out by using the MATLAB software. The simulation results show that increasing working hours can short reliability of pusher hydraulic system, and its reliability decrease rapidly first along with the time, then decrease slowly gradually, the reliability can be guaranteed in the limited working time.