To address the problems of insufficient dynamic performance and torque fluctuation suppression of the ADRC controller in the servo system of permanent magnet synchronous motor (PMSM), a PMSM sliding mode active disturbance rejection control (SM-ADRC) method based on the Quasi-Proportional Resonant controller is proposed to improve the dynamic response characteristics of the system and suppress the influence of torque resonance at the same time. Firstly, in order to solve the problem of insufficient response speed and accuracy of the nonlinear state error feedback control law in the traditional active disturbance rejection controller, a control law combining the global fast terminal sliding mode surface and the improved approach law is designed to enhance the anti-interference ability of the system and improve the dynamic response performance of the system. Secondly, in view of the rotational speed fluctuation problem caused by the current sampling error during the operation of PMSM resulting in double fundamental frequency resonance, a Quasi-Proportional Resonant controller is introduced to enhance the suppression ability of double fundamental frequency disturbances. Combined with the expanded state observer, it can effectively observe the load disturbances while improving the suppression ability of disturbances. Finally, the simulation and experimental results show that this method can enable the system to have better dynamic response characteristics, strong anti-interference ability and resonance suppression performance.