SUMMARYIn this paper, the observer-based H 1 control problem for uncertain singular time-delay systems with actuator saturation is concerned. First, a delay-dependent linear matrix inequality (LMI) condition is obtained which, guarantees that the uncertain singular time-delay systems with actuator saturation are regular, impulse free, and asymptotically stable with H 1 performance condition. Then, with this condition, the estimation of stability region and the design method of observer-based H 1 controller are given by solving LMIs and convex optimization problem. Finally, some numerical examples are provided to demonstrate the merit of the obtained results.