To deal with the model uncertainties and unknown external disturbances in the process of attitude control of quad-rotor aircraftsa novel Non-singular Fast Terminal Sliding Mode Control (NFTSMC) method based on Finite-Time Disturbance Observer (FTDO) is proposed.FirstlyFTDO is designed to observe the model uncertainties and unknown external disturbances in real timeand a novel NFTSMC controller is designed based on observed values.The proposed control law can not only depress the model uncertainties and unknown external disturbancesbut also improve the tracking speed and control accuracy of the system.The stability of the control system is proved through Lyapunov theory.Finallythe simulation results demonstrate the effectiveness of the proposed control method.