This paper describes a development of the mobile manipulator with the control of ifs gravity center position. Since 1988. We have presented the three degree-of-freedom manipulator with the control of its horizontal gravity center position by using one kinematics redundancy on two dimensions Cartesian coordinates (horizontal and vertical one). So, adding mobility to this manipulator, we developed the mobile manipulator It is a characteristics of this mobile manipulator that control method to only gravity center position of this manipulator system, not including gravity center position of mobile system. Further we present the compensation method for the inertia force in the mobile system moving.