Based on the force model of the ball in the cage type constant velocity universal joint,the expressions of the circumferential force of the groove on the steel ball,the normal contact force of the channel to the steel ball and the normal contact force of the cage window to the steel ball are deduced when the steel ball moves in the inner groove and the bell shaped outer channel of the star sleeve. On this basis,based on the Herzt contact theory,the above force is verified by Adams dynamics.The results show that the simulation results are basically consistent with the theoretical calculation. The circumferential force,the normal contact force,the friction force of the steel ball and the star sleeve and the friction force of the seven channel cage type constant velocity universal joint are less than that of the six channel,and they change with the change of the swinging angle.