Abstract: This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state, control input and interconnections. A novel scheme, viewing the interconnections with time-varying delays as effective information but not disturbances, is developed. Based on Lyapunov stability theory, using various techniques of decomposing and magnifying matrices, a design method of the non-fragile decentralized guaranteed cost controller for unperturbed neutral large-scale interconnected systems is proposed and the guaranteed cost is presented. The further results are derived for the uncertain case from the criterion of unperturbed neutral large-scale interconnected systems. Finally, an illustrative example shows that the results are significantly better than the existing results in the literatures.