This paper investigates the formation problem of multiple robots based on the leader–follower mechanism. At first, the dynamics of such a leader–follower framework are modeled. The input–output equations are depicted by calculating the relative degree of a leader–follower formation system. Furthermore, the derivative and integral terminal sliding mode controller is designed based on the relative degree. Since the formation system suffers from uncertainties, the nonlinear disturbance observer is adopted to deal with the uncertainties. The stability of the closed-loop control system is proven in the sense of Lyapunov. Finally, some numerical simulations are displayed to verify the feasibility and effectiveness by the designed controller and observer.