The formation control of UAV under the leader-follower structure is explored. Aiming at the problem that traditional formation control relies on external positioning equipment and communication equipment, an adaptive event-triggered formation control method based on bearing information is designed, which measures the relative bearing by utilizing on-board camera to reduce the dependence on external equipment. A fuzzy system is further designed for the modeling error and external disturbance of the formation system, and anovel bearing formation controller is designed by combining the event-triggering mechanism, adaptive strategy and inversion control. This method not only realizes the formation control, but also avoids the continuous update of the control law, thus saving the computational resources of the UAV. Subsequently, the stability of the closed-loop control system is proved based on Lyapunov theory. Finally, the effectiveness of the proposed controller is verified by simulation experiment.