This paper is concerned with decentralized robust control design for a class of interconnected systems with time-varying uncertainties. The interconnected systems under consideration contain time-varying uncertain parameters whose values are unknown but bounded in given compact sets. Sufficient conditions under which a considered system can be quadratically stabilized by a linear decentralized feedback control for all admissible variations of uncertainties are given in terms of the structures of uncertainties. For the interconnected systems satisfying the stabilizability conditions, a decentralized control design procedure is also provided.