In this note, the problem of Hinfin filtering for a class of discrete-time switched systems with state delays is investigated. Attention is focused on the design of a stable filter guaranteeing a prescribed noise attenuation level in the Hinfin sense. By using switched Lyapunov functionals, sufficient conditions for the solvability of this problem are obtained in terms of linear matrix inequalities (LMIs), by solving which a desired Hinfin filter can be constructed. A numerical example is provided to demonstrate the effectiveness of the proposed techniques