With the increasing number of the UAV swarm, the continuous expansion of combat space, the gradual complexity and diversity of tasks and the limited information conditions, how to deal with the distributed cooperation of the UAV swarm under complex constraints has become the key problem faced by the UAV swarm system. Swarm intelligence is becoming a new collaborative model. Its basic idea is to solve the problem of distributed collaboration of UAV swarms by imitating the high self-organization of biological groups. Therefore, this paper discriminates the important concepts and summarizes the research status of biological group behavior mechanism and model, the distributed cooperative method of the UAV swarm and its application, and emphatically analyzes four key development directions, providing reference for the future development of the UAV swarm.