Based on the theory of robust l2 – l∞ filtering, this paper is concerned with the problem of robust l2 – l∞ filtering for polytopic uncertain discrete time-delay systems. Sufficient conditions are established in terms of linear matrix inequalities for the existence of filters guaranteeing a prescrebed energy-to-peak disturbance attenuation level for all possible uncertainties and time delays. The admissible filter can be found by solving a convex optimization problem. The numerical example is given to demonstrate the applicability and the effectiveness of the proposed approach.