The invention discloses a method and system for controlling double-fed wind turbine generator emergency power support. According to the technical scheme, the method includes: calculating the frequencyof a power grid and the real-time active power and real-time reactive power of a double-fed wind turbine generator; according to the power grid frequency combining with dead zone setting, judging whether the double-fed wind turbine generator enters an emergency power support mode or not; if so, by the double-fed wind turbine generator, using kinetic energy stored in a rotor to perform fast powersupport; when the power grid frequency recovers to a value in the dead zone range, by the double-fed wind turbine generator, starting power recovering, and entering reactive power damping control. Themethod has the advantages that virtual inertia is achieved by the control strategy of the double-fed wind turbine generator, the double-fed wind turbine generator can fast perform emergency power support during power grid frequency disturbance, system damping is improved during frequency modulation recovering by the emergency power support combining with reactive power control, system frequency oscillation is suppressed, and the secondary impact of frequency can be prevented.