Abstract: Research on the use of SMO for controlling PMSM,in order to improve the control accuracy of PMSM. Firstly, the PMSM is modeled, and then the control strategy of PMSM based on SMO is presented. The designed control strategy is simulated by using MATLAB software, and the simulation operation curves of the starting speed, variable speed operation and sudden load addition of the PMSM are obtained. The simulation results show that the dynamic performance of the PMSM control based on SMO is good, the system response is fast, and the tracking accuracy is high.