A wind energy converter mainly comprises an installation box, a fan, a shaft pin, an energy storage device, a power generation device and a power source output interface. A wind blows the fan, the fan drives the shaft pin to rotate, the shaft pin rotates to tighten a spring and accordingly mechanical energy storage is achieved. Then, mechanical energy is transferred to the power generation device in the reset process of the spring to be converted into electric energy and output by the power source output interface; the mechanical energy can be stored under the wind condition by locking a locking pin or opening a transmission gear. The mechanical energy can be converted into the electric energy to be output by opening the transmission gear again when it is needed.