The utility model discloses a wind driven generator system based on flywheel energy storage speed regulation. The wind driven generator system comprises a fan blade, a wind wheel axis, a flywheel, a main shaft and a generator. The fan blade is fixed at one end of the wind wheel axis, a circular hole is formed in the end face at the other end of the wind wheel axis, ratchets are arranged on the inner wall of the circumference of the circular hole, a ratchet wheel is arranged on the flywheel and stretches into the circular hole, and detents are arranged on the ratchet wheel and matched with the ratchets. The flywheel, the main shaft and the generator are connected sequentially, fixedly and coaxially. When wind power is strong, the flywheel is utilized to store redundant wind energy; when the wind power is weak, the wind energy stored through the flywheel is released to drive a motor. Meanwhile, the flywheel allows the speed of the motor to be stabilized within a certain range, fluctuation of electric energy outputted by the generator caused by wind power fluctuation is eliminated, and thus the purpose that quality of the electric energy is improved is achieved. The wind driven generator system is directly installed on a wind generating set by the adoption of a mechanical mode and belongs to conversion of mechanical energy, conversion frequency is reduced, and loss is lowered.