In order to study the obstacle avoidance control effect of unmanned aerial vehicle (UAV) anti-collision formation in the environment of strong electromagnetic interference, the ultraviolet light communication model between UAV formations was adopted, and the traditional artificial potential field method was improved. The potential field function of the UAV and the obstacle was established, with which the local obstacle avoidance while the UAV formation was flying was realized. The results show that with the improved artificial potential field method, the obstacle avoidance time reduces by 7.38% and the total obstacle avoidance path reduces by 5.8% compared with the traditional artificial potential field method under the same conditions. The improved obstacle avoidance algorithm is applied to the formation. It can realize the obstacle avoidance between the drones and the avoidance of external obstacles, the formation can maintain a fixed formation to fly to the target point. This result has certain application value for the research of UAV formation obstacle avoidance in strong electromagnetic interference environment.