A fuzzy backstepping adaptive controller with a command filter was designed for a fixed-wing aircraft to overcome the problems of the restricted state and actuator′s physical characteristics during the flight control process.First,the MIMO strict feedback system with error terms was developed.Secondly,a fuzzy system was developed to approach the error terms of the subsystem online,and the virtual control law was designed for each subsystem based on Backstepping method.Thirdly,considering the state constraints and the physical characteristics of actuators (including the constraints of amplitude and rate),a command filter with constraints on amplitude,rate and bandwidth was introduced into the designed virtual control law to compensate for the filter error term.Finally,Lyapunov stability theorem was used to prove that the closed-loop system is guaranteed to be bounded,and the tracking error converges exponentially to a small neighborhood around zero.The simulation results show that the designed controller has strong stability and robustness.