Provided is an electronic device including a rotary power generation device using an electret, which is capable of preventing a spiral spring from being wound up or fully extended. The electronic device includes a power generation mechanism including: first rotary member, which is supported in a freely rotatable manner, and has a center of gravity shifted from a rotation center; second rotary member supported in a freely rotatable manner; an elastic member configured to elastically connect the first rotary member and the second rotary member to each other for rotary motions thereof; a stationary member arranged so as to be opposed to the second rotary member; and an electret film formed on a surface of any one of the second rotary member and the stationary member.