This paper deals with the discrete-time H^∞ fixed-lag smoothing problem. Conventionally, this problem is solved by reducing it to a standard H^∞ filtering problem for a higher order system that includes not only the actual system dynamics but also the delay caused by the smoothing lag. Such an approach may suffer from computational problems as the smoothing lag gets larger, especially due to the fact that a high dimensional Discrete Algebraic Riccati Equation (DARE) is to be solved. To overcome this disadvantage, in this paper, a new solution to this problem is derived in terms of one DARE of the same dimensions as the actual system dynamics.