The invention discloses a method for decoupling torque control and variable pitch control of a wind generating set, and belongs to the fields of variable speed and variable pitch of a fan. According to the method, decoupling of fan torque control and variable pitch control is achieved through switching of different states, three different states are included, and the values of torque output Tout and pitch angle output Pout are different in all the states. Switching conditions between the different states are defined. The invention further discloses a system for decoupling torque control and variable pitch control of the wind generating set. The system comprises a rotating speed measuring mechanism, a state machine, a torque executing mechanism and a variable pitch executing mechanism. Thestate machine realizes decoupling of torque control and variable pitch control of the wind generating set by applying the decoupling method. Torque output and pitch angle output in different states are controlled by adopting the different states of the state machine, switching of the different states is achieved according to the real-time fan measurement rotating speed, decoupling of fan torque control and variable pitch control is achieved, and the rotating speed and power of the variable-speed variable-pitch wind turbine generator are more stable.