A power generation device converts vibrational energy into electric power using a vibrational power generation element in which an electret is provided on one substrate of substrates configured to be relatively movable while maintaining a mutually facing state, and supplies the electric power. A vibrational power generation element has the same configuration as the vibrational power generation element and converts vibrational energy into electric power. The vibrational power generation element is connected to a light-emitting diode via a bridge-type full wave rectifier circuit constituted by diodes, a smoothing circuit constituted by a capacitor, and a light-emitting diode drive circuit. A power generation state of the power generation device using the vibrational power generation element and the like is displayed by blinking of the light-emitting diode.