An automatic power-generation light-image fan device is described. It has a fan motor, a vane set, a circuit board, a programmable chip, an automatic power-generation component, a rectifier filter circuit, a magnetic sensor and a positioning magnet. In this device, the circuit board is mounted on the vanes of the vane set and also has plural light-emitting elements, which are respectively connected to I/O terminals of the programmable chip, and an accommodating room is mounted on an inner surface of the vane set, in which an inner circular surface of the accommodating room is circularly mounted by an inductance coil whose ends are connected to an input terminal of the rectifier filter circuit. Thereby, the light-emitting elements mounted on the fan can be controlled to generate various different twinkling light-image variations and an effect of persistence of vision when the fan motor is rotating.