Abstract: [Objective] The output terminal of the permanent magnet synchronous motor (PMSM) drive system is often connected to an LC filter, which is used to eliminate high-frequency voltage pulse. However, the introduction of an LC output filter can induce inherent resonance, leading to instability in the PMSM control system. In order to suppress the resonant caused by LC output filter in permanent magnet synchronous motors drive system, a resonance suppression strategy based on active damping via capacitor current feedback is proposed at the paper. [Methods] Firstly, a mathematical model of the PMSM control system with LC output filter was established. Meanwhile, the causes of resonance were analyzed and located by analyzing the transfer function and Bode diagram of the control system. Then, a control method based on active damping of capacitive current was designed. The effectiveness of the method was analyzed and confirmed by the frequency domain perspective. Subsequently, in order to ensure the stability of the control system, the parameter design of the current regulator and the design of the active damping coefficient was carried out. To verify the effectiveness of the proposed method, it was compared with traditional vector control methods and passive damping control methods. [Results] Compared with traditional vector control methods, the capacitor current active damping control strategy proposed in this paper has a small overshoot and response time, which exhibited better stability. Compared with passive damping control methods, the proposed strategy achieved a good solution to the resonance problem of the control circuit without increasing hardware, which showed good anti-interference ability in the case of sudden load loading and unloading.[Conclusion] The above work indicates that, for PMSM control systems with LC output filters, the capacitor current active damping method proposed in this paper can achieve smooth control of motor speed and effectively solve the problem of control system resonance.