To address the issues of current harmonics generated during the operation of Permanent Magnet Synchronous Motor (PMSM), which lead to reduced efficiency, lifespan, and stability of the motor, an improved harmonic current suppression method is proposed. Firstly, building on the current mean value method for harmonic current extraction, a combination of a low-pass filter and the improved current mean value method (LPF-CAM) is employed. This results in a new current harmonic extraction method based on LPF-CAM, which enhances the accuracy of harmonic DC component extraction. Subsequently, a harmonic compensation voltage acquisition method based on a PI controller is used to generate compensation voltage for harmonic current suppression. Compared to traditional methods, this strategy simplifies control system design and reduces computational complexity, offering high practical value and potential for wide application. Simulation and experimental results show that this strategy effectively suppresses harmonic current and improves the stability of the Permanent Magnet Synchronous Motor.