Abstract. In this paper, the robust In this paper, the robust f H control problem of output dynamic observerbased control for a class of uncertain neutral systems with discrete and distributed time delays is considered. Linear matrix inequality (LMI) optimization approach is used to design the new f H output dynamic controls.The minimal f H -norm bound and the maximal perturbed bound are given. Based on the result of this paper, the constraint of matrix equality is not necessary for designing the f H observer-based controls. Finally, a numerical example is given to illustrate the efficiency of the proposed approach.