Objective To study the trajectory equation based on the transporting process of palletizing robot. Methods D-H method was adopted to establish the positive and inverse solutions equation of the robot爷 s space trajectory, and to obtain the angle variation relative to the initial position at each joint. Dynamics simulation was conducted after adding angle drive to the corresponding joint drive by applying five-order polynomial approximation methods, achieving the path curve of the robot. Results The parameter equation of space curve was obtained by using the Matlab curve fitting toolbox and the points in the trajectory curve, and the rationality of curve equation was compared. Conclusion The method of simulation analysis and data fitting could avoid complex mathematic modeling and formula calculation, consequently, it to a great extent reduced the amount of calculation and working hours, moreover, it provided theoretical basis and technical support for completing the design of the control system.