Abstract: The robust decentralized stabilization based on observer was discussed on a class of uncertain interconnected time-delay systems in which the time-varying parameter uncertainties are unknown and norm-bounded. The delayed terms are found in all the system state, control input and interconnection terms. Based on Lyapunov stability theory and linear matrix inequality (LMI) technique, a decentralized output feedback controller is designed so that the closed loop large-scale interconnected system is asymptotically stable with a sufficient condition for the stability derived in terms of LMIs. The simulation is given to illustrate the validity of the proposed methods.