Abstract: To address the issue of degraded control performance caused by unknown disturbances in the inner loop of a magnetic levitation bearing current, a model of the magnetic levitation bearing switching power amplifier under unknown disturbances was developed. Based on this model, a sliding mode disturbance observer was designed to estimate the unknown disturbances. At the system control end, the equivalent input disturbance method was employed to perform feedforward compensation on the estimated disturbance values, and an integral sliding mode controller was used to enhance the system’s robustness. Compared to PI control algorithms and integral sliding mode control, this method demonstrates superior dynamic response performance and disturbance rejection capability under various operating conditions. Simulations have validated the effectiveness of the proposed method.