In this paper, a localized control problem is formulated for large-scale systems: The disturbance propagation into or from a local target part of the system is inhibited by local control. As a preliminary, the parametrization of all stabilizing local controllers is introduced. Then, by specializing the parametrized controller, we give the solution to the localized control problem. Finally, the proposed controller is applied to a power network system. The use and effectiveness are demonstrated in the frequency control of the system.