A control strategy based on disturbance compensation is devised to address the issue of stabilizing trajectory tracking for quadcopter unmanned aerial vehicles （UAVs） with unknown external disturbances. Firstly， this paper designs a PID position controller for the quadcopter UAV’s position loop and compensates for external disturbances using a disturbance observer. Secondly， the desired attitude is obtained through attitude computation， and an incremental nonlinear dynamic inversion（INDI） attitude controller with strong robust performance is designed for the quadcopter UAV’s attitude loop. Finally， simulation and comparative experiments are conducted by Simulink. Experimental results indicate that this control strategy can achieve trajectory tracking capability for quadcopter UAVs under conditions of unknown external disturbances.