A vibration power generator configured to generate power by displacement between an electret group having a plurality of electrets and an electrode group having a plurality of electrodes in a relative movement direction in response to an external vibration, includes a casing in which the electret group and the electrode group are disposed, a fixed member in which one of the electret group and the electrode group is disposed, the fixed member being fixed to a side of the casing, and a movable member in which the other of the electret group and the electrode group is disposed. The movable member is disposed in the casing such that the movable member is relatively movable in response to the external vibration while opposed to the fixed member.