This paper deals with the problem of H^∞ detection filter design for discrete-time systems with multiple time delays, where methods for decoupling the fault effects from unknown inputs including model uncertainties and external plant disturbances are not available. Through the appropriate choice of the filter gain, the filter is convergent if there is no fault in the system, and the effect of disturbances on residual is minimized in the sense of H^∞ norm. The problem of achieving satisfactory sensitivity of the residual to faults and its solution are formulated. The detection threshold of the filter is also discussed. Finally, simulation of a numerical example is made to illustrate the efficiency of the proposed method.