The problem of $H_{infty}$ filtering for discrete-time systems with time-varying delay in measurement is investigated in this paper. First, under the assumption that the time-varying delay is of a known upper bound, the delayed measurement is re-described as the one with multiple state delays. Then the proposed Hx filtering problem is transformed into one for systems with multiple measurement channels that contain the same state information as the original measurement and each channel has a single constant delay. Finally, based on the reorganized innovation analysis approach in Krein space, a necessary and sufficient condition for the existence of an $H_{infty}$ filter which guarantees a prescribed attenuation level is derived. The solution to the $H_{infty}$ filtering is given in terms of the solutions to Riccati and matrix difference equations.