Based on the particularity of the racing field of the Baja SAE China, the Baja Racing Team of our university has adopted rzeppa universal joint for vehicle design and field competition in the semi-axle parts of the race car in previous years. In view of the complex conditions of the Baja Competition, such as gravity test, climb test, handling test, endurance test, etc., it is necessary to optimize and develop a more convenient maintenance model. Installation and use of better performance, more suitable for off-road conditions of the shaft. In this paper, based on the development dynamics of automobile axles and the transverse comparison of various axles, a kind of telescopic cross-shaft universal joint axles is designed by using CATIA software to model and simulate kinematics and dynamics by using ANSYS software. At the same time, the stress and strain of the model are continuously optimized according to the change of axle wheel Angle and the torque matching of Baja Racing. The object rotation experiment is designed, and the transmission efficiency of the universal joint of the cross shaft is simulated and analyzed by MATLAB. According to the analysis data and experimental test, the results show that the transmission efficiency, reliability and maintainability of the cross shaft universal joint can fully meet the actual field conditions of the Baja Competition. In addition, this paper also puts forward the optimization scheme and suggestions for improving the transmission efficiency, extending the life and improving the durability of the cross shaft universal joint which may need further research.