Abstract: A new control method based on potential function is presented,which can effectively analyze the stability of the formation of a multiple robot system and can control the formation in a distributed manner.Proper potential functions related to the object and the structure of the formation is chosen,and a new distributed control law is designed with graph theory and Lyapunov stability theory,which can stabilize the formation of the multiple robot system and can track the object effectively.The sufficient condition for the solvability of the formation control of multiple robot system is given.Numerical simulation proves the validity of the proposed formation control law.