Abstract: For problems inherent in the stepper motor control on high precision occasions, an optimized current control strategy is proposed based on the field programmable gate array (FPGA). By using an asynchronous trigger to chop the pulse width modulation (PWM) signal with a constant frequency, the switching frequency and coupling interferences of the ground signal are reduced. In addition, by adopting the fast and slow mixed current decay mode the stepper motor responds rapidly when running at high speed, while a low current ripple is obtained when running at low speed. The method is then tested on a high precision micro-manipulator, and experimental results meet the requirements of various indicators with a high running accuracy and low noise. The proposed method is not only suitable for high-precision control, but it can also be applied to a multiaxis servo control system, and is facilitated for extension and transplantation.