In order to improve the control performance of brushless DC motor, the motor control system based on digital signal processor (DSP) TMS320F2812 is designed. To be able to design the reasonable control system, the control principle of the brushless DC motor is analyzed firstly. On the basis of this principle, and the dualclosed loop control system for a brushless DC motor is designed, and completed this control system from two aspects of hardware and software. The simulation experiment of the control system is carried out with MATLAB, and then analyzed the noload and load simulation waveform changes, this speed control system is validate has the advantages of stably and rapidly starting speed, perfect speed performance and better control precision and so on , it has very high practical value.