The invention relates to a torque determining method and a type selection method and device of a wind driven generator set variable-pitch motor and belongs to the technical field of wind driven generation. The working conditions of the wind driven generator set are set by establishing a fan simulation model, and a blade root portion torque, an overturning moment, an axial force, a radial resultant force, power, rotation speed and the acceleration speed of a variable-pitch bearing are calculated; a mathematical model is established, the friction force of the variable-pitch bearing is determined, and then a driving torque and a braking torque of the variable-pitch bearing are solved; the variable-pitch motor is finally selected according to a rated driving torque, a maximum driving torque and a braking torque of the variable-pitch motor. The device comprises a variable-pitch motor torque calculating module, a variable-pitch motor maximum torque and rated torque calculating module and a variable-pitch motor type selecting module. The device has the advantages of being simple in principle, easy to operate and high in accuracy, the variable-pitch motor is reasonably selected on the premise that normal operation of a large wind driven generator set variable-pitch system is ensured, reduction of the fault probability of the variable-pitch system and the manufacturing cost of a large wind driven generator set are promoted, and the market competitiveness is improved.