The invention discloses a method for controlling a double-fed wind power plant capable of improving the transient stability of a power grid. According to the method, the total power of wind power plant grid connection points is used as the controlled quantity, when the power grid breaks down, a wind power plant control center is used for detecting the frequencies and voltages of the wind power plant grid connection points in real time, active power output and reactive power output of the wind power plant can be adjusted according to the frequency deviation, the voltage deviation and the voltage change ratio of the power grid, the active power control quantity and the reactive power control quantity are distributed to all sets and SVCs. Attenuation of system oscillation energy is accelerated, reactive power compensation is provided for the system, and the constancy of busbar voltages of the grid connection points can be maintained. By the adoption of the method, the active power output and the reactive power output of the wind power plant can be adjusted in real time according to the frequency change and voltage change of the wind power plant grid connection points, attenuation of the system oscillation energy is accelerated, the reactive power compensation is provided for the system, the transient state power angle stability of the power grid can be improved, and the transient voltage stability of the power grid can be improved.