Abstract: The integrated design problem of feedback controller and robust fault detection filter is studied for uncertain linear time invariant system. By introducing a performance index, the fault detection filter design problem can be formulated as an optimization problem and the solution can be obtained in terms of Riccati equation. In the case of feedback controller and fault detection filter sharing a common observer, a two-objective optimization approach to integrated design feedback controller and fault detection filter is proposed such that the closed-loop feedback control system performance and robustness of fault detection filter can achieve their optimal level simultaneously. An illustrative example shows the effectiveness of the proposed methods.