In this paper, the problem of non-fragile observer-based H_∞ control for discrete-time switched delay systems is investigated. Both data missing and time delays are taken into account in the links from sensors to observers and from controllers to actuators. Such problem is transformed into an H_∞ control problem for stochastic switched delay systems. Average dwell time (ADT) approach is used to obtain sufficient conditions on the solvability of such problems. An example is provided to show the effectiveness of the proposed method.