The invention relates to a maximum wind energy capturing method of variable-speed wind generating sets. The method includes that current optimum rotary speed of a plurality of wind generators is estimated by capturing conditions of wind energy through the wind generators within previous control periods and is taken as the input of a controller, errors are reduced through proportional control on the basis of an indirect speed control algorithm, the optimum rotary speed in tracking the wind generators is realized, and the maximum output power is acquired. With the method, precise modeling of the wind generators is not needed, nor is measuring of wind velocity; simpleness in structure is achieved, parameters are easy to adjust, production energy is higher than that by a maximum wind energy capturing method and a speed velocity indirect control method which are commonly used in industry, influence of environment factors and structural changes of the wind generators on energy generation can be weakened, a control objective that most of the wind generators are lower than rated wind velocity sections can be met, and great application values are achieved.