Abstract: In this study, the leader-follower finite-time consensus problem of second-order multi-agent systems with unknown external disturbances is investigated. To address this problem, different from existing works, a novel time-varying finite-time disturbance observer is designed, and a kind of super twisting integral sliding mode control protocol is proposed. Second, using Lyapunov theory and graph theory, it is proved that second-order nonlinear multi-agent systems with unknown disturbances exponentially reach consensus. Finally, a simulation example is included to verify the effectiveness of the theoretical results. The simulation shows that compared with the common sliding mode algorithm, the new protocol can not only reduce the chattering effectively but improve convergence speed.