A wave-power electricity generating device capable of efficiently generating electricity using ocean waves of various frequencies. A wave-power electricity generating device is provided with: a vibration receiving section (31) which is provided within a float body floated on a wave surface and which generates electricity by means of vibration applied thereto; a mass body (4) which applies mass to the vibration receiving section (31) from thereabove; elastic members (5) which serially support the mass body (4); and lock mechanisms (6) which individually restrain and release the motion of the elastic members (5).
