The invention discloses a two-degree-of-freedom congestion control method and device, wherein the technical problems of round-trip time and extra interference in a wide-area power system in the prior art are solved; the technical problem of round-trip time is solved by performing internal model control on the wide-area power system of a traditional Smith congestion controller and designing a feedback controller according to the internal model control theory; extra interference in the wide-area power system is filtered out by designing an anti-interference controller based on frequency analysis; and a two-degree-of-freedom congestion controller is designed according to the feedback controller and the anti-interference controller, and an input-output relational expression of the wide-area power system is calculated after the processing of the two-degree-of-freedom congestion controller to realize two-degree-of-freedom congestion control of the system. The invention provides a guarantee to the effective power output of the wide-area power system.