The transportation of the substrate is the main component of the digital ink jet printing machine. In order to improve the stable operation of the digital ink jet printing machine, the MATLAB / Simulink simulation of the motion control system of the substrate is carried out. Firstly, the basic principle of the motion control system of the printer is described, and the characteristics of the servo motor and the stepper motor are compared and analyzed. Then the servo control principle of the permanent magnet synchronous motor is introduced. Finally, the motion control of the digital inkjet printing substrate The system is modeled and the simulation of SVPWM control system is carried out on the permanent magnet synchronous motor drive, which realizes the fast response speed, speed and torque control performance of the substrate movement system. The experimental results show that the method improves the accuracy and stability of the printing system of digital inkjet printing system to a certain extent.