Abstract: A scheme of UAV base station as a dynamic relay in emergency communication environment is proposed and simulated, and a path planning scheme of regional relay for single UAV relay is designed. Considering the performance of existing UAVs and relay nodes comprehensively, the coverage of UAV relay can be maximized and the residence time of relay nodes can be maximized under the condition that the UAVs can return home. Based on the UAV relay equipment, the single UAV relay cruise support communication can be realized in the case of equipment shortage in emergency communication, and the multi-UAV relay tether relay service can be realized by determining the relay point in the case of abundant equipment. The location of relay nodes was determined based on particle swarm optimization (PSO) to ensure the reasonable and accurate location of relay nodes. The simulation experiments were repeatedly verified by various parameters and data to ensure the reliability of the algorithm, and the algorithm accuracy and time were considered comprehensively. The simulated annealing algorithm was used to optimize the UAV path to ensure that the UAV path was the shortest.