Due to the underactuation and strong coupling of quadrotor UAVs, the visual servo effect of the camera fixed on the UAV airframe is not good.To solve the problem, an image moment based visual servo method is proposed.Firstly, the virtual image plane is built to select image moments as features, and then image dynamics is decoupled.Furthermore, the servo relationship between image errors and velocity is established by using the quadrotor dynamics model.Secondly, according to the dynamic decoupling of the quadrotor, the system is decoupled into position controller and attitude controller.The velocity control law is obtained by the position controller according to the servo relationship, and the desired attitude is obtained directly by means of dynamic expansion.Finally, a sliding mode controller is designed for attitude tracking control aiming at the attitude disturbance caused by the nonlinearity of the system.Simulation results verify the superiority and robustness of the proposed method.