According to the analysis of mathematical model for permanent magnet synchronous motor (PMSM), direct torque control(DTC) technology is introduced to the control system of PMSM. The paper builds dual-closed loop control system of PMSM, and the outer loop is speed loop, the inner loop is flux and torque loop, at the same time, the paper makes simulation in Matlab/Simulink. The simulation results show that the DTC technology significantly improves the dynamic performances of PMSM, and the control system is no overshoot, and has small flux response comparing with the conventional control methods of PMSM. So the application of DTC technology in PMSM provides a new thoughtful way for PMSM control system designing and debugging in actual application.