Abstract: This paper considers the issue of robust H∞ guaranteed cost control for a class of uncertain It-type stochastic systems with time-varying delays. State-feedback guaranteed cost controllers are presented based on Lyapunov-Krasovskii functional approach. For all admissible uncertainties, the designed controllers ensure that the closed-loop systems are robustly stochastically exponentially stable in a mean-square sense with a prescribed H∞ disturbance attenuation level γ. Sufficient conditions for the existences of desired controllers are formulated in terms of linear matrix inequalities (LMIs). The design problems of the optimal guaranteed cost controllers for the uncertain stochastic time-delay systems are cast into convex optimization problems with LMIs constraints. A numerical example is provided to demonstrate the effectiveness of the proposed method.