To simulate the car-to-car crash accidents in the real field, the Autonomous Driving System was developed. This system consists of communicating, sensing, accelerating, braking, steering and data recording subsystems. All these were designed to be compact, light and collapsible, so that the crash characteristics of test vehicle were not affected.The velocity performance of the system covers from 10 kph to 100 kph within ± 0.5 kph error, and the lateral deviation is constrained within ± 20 mm.With this system, several frontal offset and side car-to-car crash tests were carried out successfully. Deformations, injury levels, deceleration signals and dynamic behaviors during crash were typically investigated. And the dynamic behaviors were compared with the simulation results of EDSMAC.Car-to-car crash tests between small and large vehicles with different masses were carried out and the effects on the compatibility were investigated.