Abstract： A fault tolerant consensus problem for multi-agent systems with actuator faults and exterior disturbance was investigated, where the actuator fault was characterized by gain variation. An adaptive-gain compensating control law was added to the nominal control input to ensure consensus. Relative output information rather than state information was utilized to design the control law. By analyzing the stability of the closed-loop tracking error systems, a sufficient condition for consensus of the original system was proposed. It is shown that as long as the control input of leader agent and the exterior disturbance are bounded by some positive constants, fault-tolerant consensus can be realized by appropriately choosing the design parameters. A numerical simulation validates the main results.