Electromechanical servo system has unmodeled dynamics and unavoidable unknown disturbances,which will seriously affect the servo performance of the system.Aiming at the problem of angular displacement tracking control of inertial load of electromechanical servo system under unknown disturbance,and considering the influence of unmodeled dynamics on the system,a fuzzy adaptive command filtering control method based on finite time was proposed.It could effectively compensate the unknown disturbance and unmodeled dynamics in the system,and had a good effect of angular displacement tracking control of inertial load.To deal with the unknown external disturbance and unmodeled dynamics in the system,combining the filter backstepping method and the fuzzy control theory,the fuzzy logic system was used to approximate the unknown nonlinear dynamics while constructing an adaptive controller.At the same time,considering the computational explosion caused by differential calculation,a finite time instruction filter was constructed to reduce the computational complexity of the system.And a filtering error compensation mechanism was designed to compensate the filtering error term ensuring the approximation ability of the filtering signal,and improving the tracking control performance of the system.Based on stability analysis,it is proved that the tracking error of the system can converge in a finite time under the presented control scheme.Finally,the effectiveness of the proposed control scheme is proved through simulation study.