The work aims to propose a new design method for the anti-integral windup PI current controller, in order to improve the production efficiency of continuous packaging machine. With respect to the excessively slow response speed for the stepping motor winding current caused by the integral windup of PI controller, the size of anti-windup gain value was determined and the integral action effects were adjusted according to the input and output states of the controller. When the input changed slowly, this controller gave the full play to the integrator to reduce the overshoot; when the input changed quickly, the integrator withdrew from the windup more quickly to improve the response speed of the system. The experiment results showed that, compared with the traditional PI control and back-calculation PI controller with a fixed gain, the proposed method could control the winding current more accurately, which improved the current response speed and reduced the overshoot. This method makes the winding current change with the reference value in a better way and improves the dynamic performance of the motor under different operating conditions.