For a class of uncertain linear systems, the issue of robust fault tolerant control against sensor faults (or actuator invalidation) is discussed in this paper, and a design bases on disk area pole assignment method with state feedback structure has also been present . By solving linear matrix inequation (LMI), the state feedback control gain vector has been obtained, the controller design by this way keeps integrity and stability. Simultaneously, In order to overcome the drawback of general robust fault tolerant control, we design a robust observer to estimate fault status of the plant , and the sufficient conditions which ensure the robust state feedback stability and robust observer asymptotic stability are also given. By means of calculate the effectiveness factor, the fault of the plant has been detected and isolated. Finally, a numerical example is given to illustrate the design plant. Simulations with applications in hydraulic turbine Regulator demonstrate the efficiency of the proposed design, and give the excitable overall performance of the control system.