Abstract: In order to better control the operation of the hydraulic manipulator in industrial production, the 6R hydraulic manipulator is taken as the research object, the improved D-H method is used to model it, and the forward kinematics equation is established. Eight sets of solutions for the angle variables of each joint of the manipulator are obtained. The robotic arm is modeled by Robots Toolbox in MATLAB software, the motion trajectory of the robot was simulated in the joint space, and the smooth curves of angular displacement, angular velocity and angular acceleration of each joint axis with the time were obtained. The simulation results proved that the kinematics equation established is correct and the parameters of the robot are reasonable. It provides the necessary theoretical basis and correct kinematics model for the subsequent motion planning and real-time control of the hydraulic manipulator.