In this paper, the problems of actuator fault detection and isolation based on observers for uncertain nonlinear systems are discussed. Under some assumptions, an adaptive and robust observer design is developed. The observer is adaptive one because an adaptation law which can adjust the Lipschitz constant of Lipschitz term is introduced. For this reason, the Lipschitz constant can be unknown in our design. By using a sliding model control law, the uncertain is controlled and this makes the observer being a robust. By observing the residual produced by the adaptive and robust observer, we can reach the actuator fault detection purpose because the residual is robust to the uncertain but sensitive to the fault. After this, multi-observers are used to reach the actuator fault isolation purpose. The simulation results to a real model of a seventh-order aircraft show that the proposed method is effective.