Due to the characteristics of multi-input/multi-output, strong coupling, nonlinearity and under-actuation, the quad-rotor UAVs are sensitive to the external disturbances. To solve the problem, a control system based on Integral Backstepping is proposed. Firstly, the dynamic model of quad-rotor aircraft is established. Then, a double closed-loop control structure PID controller is designed with the outer-loop of the position control loop and the inner-loop of the attitude control loop, and a controller based on Integral Backstepping method is also designed, which is proved by Lyapunov stability theory.Finally, a simulation analysis is made to the two kinds of controllers with Matlab/Simulink. The results show that the controller model using Integral Backstepping design is obviously superior to the classical PID algorithm on control precision, regulating time and anti-disturbance performance.