The voice coil motor (VCM) is mainly used in small-range linear positioning scenarios. It is necessary to ensure that it has high precision and high robustness, and due to the influence of motor parameters and friction, the VCM is non-linear and time-varying. This article analyzes and establishes the corresponding second-order system model from the working principle of VCM. The control strategy adopts the combination of sliding mode control and state observer, and proposes corresponding solutions from the sliding mode surface and the approaching law direction to the chattering problem of sliding mode control. The sliding mode surface adopts complementary integral terminal sliding mode control (CISMC). On the basis of reducing chattering, the integral terminal sliding mode designed by homogeneous theory achieves finite time convergence; the reaching law adopts the power reaching law Combining with the fal nonlinear function, it can reach the sliding mode surface faster; outside the sliding mode control, the state observer (ESO) is used to perform feedforward compensation for system disturbances, etc., and a complementary integral terminal based on the reaching law is proposed. Sliding Mode Control (CISMC). According to the deduced mathematical model, the system simulation model is established in MATLAB/simulink. The simulation experiment shows that the CISMC+ESO scheme can reduce the stability error by up to 75% compared with the complementary sliding mode control (CSMC)+ESO scheme in tracking sinusoidal signals. The full tracking time is reduced by 28.5% at the maximum; when tracking the ramp signal, the steady-state error is significantly reduced, and the full tracking time is reduced by 84% at the maximum. Experiments show that it has a significant improvement in system control accuracy and robustness.