In order to solve the problem of uncertain parameters of fixed-wing unmanned aerial vehicles (UAV), a kinematic and dynamic simulation model is established, and the transfer function of the lateral and longitudinal loops is obtained by trimming and linearizing the model at typical state points. The adaptive method of model parameters (MPAC) is used to update the state feedback output, so as to realize the tracking of the lateral and longitudinal flight status. The simulation model of the lateral and longitudinal loops based on the adaptive control of model parameters is constructed, and compared with the PID control, the results show that the response time and overshoot of the lateral and longitudinal loops of the aircraft are significantly improved by adding the adaptive control algorithm of model parameters.