The invention provides an active control method of a doubly-fed wind turbine generator set. The method comprises the following steps that step 1, a wind power plant active control system issues an active power instruction Pgive to the doubly-fed wind turbine generator set; step 2, the actual rotating speed Omega r of the doubly-fed wind turbine generator set is measured, the control modes of the doubly-fed wind turbine generator set are switched, and the active power reference value Pref of the doubly-fed wind turbine generator set is set as different power values according to the control modes; step 3, the maximum operation rotate speed pitch angle control system of the doubly-fed wind turbine generator set is set to adjust the pitch angle based on the comparison value of the actual rotating speed Omega r and the maximum operation rotate speed, and therefore the stable operation of the doubly-fed wind turbine generator set is controlled. Compared with the prior art, the active control method of the doubly-fed wind turbine generator set guarantees flexible switching of the active power control modes of the doubly-fed wind turbine generator set under various wind power input conditions, guarantees stable operation, and plays a pivotal supporting role for the wind power plant to participate in management and running of an electrical power system.