This paper focuses on the study of UAV formation keeping based on velocity vector field.Firstly,the Leader-follower formation is taken as the research object,and the mathematical model of the UAV is built.Secondly,by referring to the artificial potential field method,the relative velocity vector is introduced,the attractive force function and the repulsive force function between the UAVs are given,and the modeling of the velocity vector field is completed.Under the influence of the velocity vector field,the UAVs can keep the formation and do not collide with each other.Finally,a simulation verification platform is built to verify the feasibility and effectiveness of the algorithm.