Abstract: Aiming at the problem of multi-UAV cooperative target allocation with dynamic change of target importance, considering the UAV heterogeneity and geographical environment constraints, in order to improve the overall service duration of multi-UAV systems, a multi-UAV cooperative target allocation scheduling strategy based on task relay is proposed. Three typical scheduling strategies are set as comparison algorithms, and six performance metrics, such as scheduling times and energy eciency, are fully analyzed through simulation experiments. The results show that the proposed algorithm can balance the energy consumption of multi-UAV systems, reduce the task completion time, and improve the overall endurance of multi-UAV systems.