A new robust model-reference adaptive nonlinear inversion controller is presented for a statically unstable UAV to perform fast climbing and diving maneuver, which mainly deals with the aerodynamic and control couplings and uncertain disturbances during the maneuver, as well as the unstable pitching moment caused by static instability.Firstly, the nonlinear inversion control based on state-feedback is adopted to realize the decoupling between multiple control channels.Then, the robust adaptive controller is designed based on the decoupled closed-loop system to compensate for the nonlinear inversion error and the unstable pitching moment, and attenuate the uncertain disturbances, thus to guarantee the stability of the UAV in the process of fast maneuvering.The effectiveness and robustness of the robust model-reference adaptive nonlinear inversion controller are validated through nonlinear simulations of the fast climbing and diving maneuver.Compared with the typical robust servo LQR optimal controller, the designed controller has better decoupling capacity and uncertain disturbance attenuating performance.