The invention discloses a double-feed wind power generator stator winding asymmetric fault detection method. The method comprises respectively obtaining a rotor side current signal and a rotor side voltage signal through a current sensor and a voltage sensor at the rotor side of a double-feed wind power generator; if it is determined that a sampling time is reached, converting an acquired voltage signal from a line voltage into a phase voltage; multiplying the current signal and the voltage signal of each phase to obtain a power signal of each phase; performing corresponding addition on the power signal of each phase to obtain a total three-phase power signal; performing Fourier transformation on the total three-phase power signal to obtain a rotor side power frequency spectrum graph; extracting the amplitude at 2f1 in the frequency spectrum graph as a characteristic value, f1 being a stator side electrical network fundamental frequency; and determining whether the characteristic value at a motor fault state is greater than the characteristic value at a motor faultless state by 1.2 to 1.6 times, and if so, emitting a fault alarm. By using the method provided by the invention, sensitive real-time online fault detection can be realized, the anti-interference capability is quite high, and the realization is simple.