The work aims to research the coupling modeling and precision control strategy for register system of printing press, so as to reduce register errors. The nonlinear coupling mathematical model of multi-color register system was established according to the register system’s working principle, and the linear transformation was carried out. Based on the linear model, a PID-based feedforward register error control strategy was designed, and the control effect was compared with that of the traditional PID control. Results showed that the register error caused by tension disturbance was reduced from ±20 μm to ±0.8 μm, and the register error caused by velocity disturbance was reduced from ±30 μm to ±1.5 μm. It is concluded that the feedforward PID control strategy can significantly reduce the register error and improve the accuracy of register control