For the steering engine fault of ducted fan UAV that may arise during the hovering, designing adaptive controller for attitude control. First, concentrating on modeling of the hovering state of ducted fan UAV, and getting the relationship between steering engine and attitude control. Then analyzing the impact of steering engine fault on the attitude control system basing on the control model. Finally, designing model reference adaptive controller basing on the fault model, so that the ducted fan UAV can maintain good attitude control if steering engine fault occurs during the hovering. Simulation results show that when steering engine fault occurs, the model reference adaptive controller can effectively inhibit the adverse effects brought by steering engine fault, so the attitude control system has strong adaptability and robustness.