In this paper, the six degrees of freedom mechanical arm is produced by Hyundai Corporation of Korea. The model is established by improved D-H method, and the geometric parameters of the robot are obtained, finally, an effective forward and inverse motion algorithm is proposed. The forward and inverse kinematics can be accurately predicted by simulation with MATLAB software, and the trajectory planning of the manipulator in the joint space is described in detail, finally, the workspace of the manipulator is Monte Carlo method.