Abstract: [Objective] In order to improve the disturbance resistance and robustness of the current controller of permanent magnet synchronous motor (PMSM), and to solve the overshoot and dq axis current ripple problems of traditional proportional integral (PI) control under speed and load changes, a PMSM current controller based sliding mode control with full-order observer (FO) is proposed. [Methods] Firstly, considering the inevitable disturbances such as dead time in the inverter, parameter changes, and abrupt changes, an actual mathematical model of the PMSM was established. Secondly, a FO was used to calculate the disturbance of the dq axis current model, and analyzed the influence of parameters on the observer. Furthermore, considering the observation disturbance, a PMSM dq axis current controller was designed based on sliding mode control. In addition, the stability of the FO was analyzed, and the stability of the controller was analyzed using Lyapunov functions. [Results] To verify the effectiveness of the method, Matlab/Simulink simulation platform and TMS320F28035 experimental platform were built. Comparative results demonstrated that the proposed method features a simpler structure and lower steady-state error than the other two controllers. The simulation and experimental results showed that compared with traditional PI controllers, the current controller of this method exhibits good robustness in dealing with parameter changes, load or speed changes, and can suppress dq axis current pulsation, ensuring the stability of the system. [Conclusion] The sliding mode controller with FO proposed in this paper improves the system’s disturbance resistance ability and enhances its dynamic response performance. This study provides technical support for the application of PMSM in new energy vehicles, rail transit, and related fields.