A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter’s dynamic model is divided into two subsystems,such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles’ dynamic effects and external disturbances. The global asymptotic stability(GAS) of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportionalintegral-derivative(PID) and linear-quadratic regulator(LQR) cascaded controller in the presence of wind gust disturbances. A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. control design, the helicopter’s dynamic model is divided into two subsystems, such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller has sliding mode control technique to compensate for the immeasurable flapping angles’ dynamic effects and external disturbances. The global as simulating demonstrate that the proposed controller can achieve superior tracking performance compared with the proportionalintegral-derivative (PID) and linear-quadratic regulator (LQR) cascaded controller in the presence of wind gust disturbances.