Abstract: The flexible redundant robot has better capability than nonredundant robot. It is the tendency of new generation robot arm. By using the "self-motion" of redundant robot, we can not only restrain robot arm vibration resulted from the structure flexibility, but also optimalize the joint torque. However, it can not be valid without considering the joint limits. This artical gives a dynamic algorithm with considering the-limits. This method controls joint angles under the liminitions during optimalizing joint torque.The simulation result shows the success of the aiogrithm.