To solve the brushless DC motor control precision low and instability problems, precision brushless DC motor control system based on FPGA was designed. It was composed of FPGA controller, drive circuit and current detection circuit. A new PID control algorithm in which parameters were changed automatically with the system state change was adopted. This method can effectively improve the ability and enhance its dynamic characteristics. Verified by experimental platform, the system can effectively suppress torque pulses, while reduce control time and improve system stability. The project has a certain reference and application value.