92.1 m。In order to obtain optimum structure parameters of frictional brake and contactless wheel retarder integrated system, the optimization design was used. The influence law between the main structure parameters of the integrated system and brake torque was analyzed in order to improve brake torque. Meanwhile, with the proposed method, different structure parameters was compared, simulation analysis on the automobile equipped with the integrated system and the automobile equipped with the frictional brake was performed. The results showed that the proposed optimization design could reduce automobile braking time and distance by 5.9 s and 92.1 m, respectively.