To achieve the rapid and optimal solution of the inverse kinematics of hyper-redundant robot,an inverse kinematics analysis method based on joints equivalent and partial optimization is proposed for a hyper-redundant omni-directional mobile manipulator with 9 degrees of freedom.According to the features of system structure,degrees of freedom are divided reasonably on the basis of separating position and posture.The position of wrist is obtained from the posture of end-effector and the minimal movement of the joints is taken as objective function,then the two-joint optimization problem which determines the height of wrist is converted to the problem of conditional extreme for 2-variable function.By this way,the redundancy of the system is effectively used while solving the problem quickly and precisely.The simulation shows that this method can satisfy the requirements of real time,accuracy and optimization.