To allow formation of an insulation film to be applied even to a glass substrate without depending on a substrate material so as to improve pressure generated by an electrostatic actuator, as well as to achieve improvement in driving stability and driving durability of the electrostatic actuator at a low cost. [Solving Means] An electrostatic actuator including an individual electrode 5 formed on a substrate, a vibration plate 6 arranged opposite to the individual electrode 5 via a predetermined gap and a driving means for causing a displacement of the vibration plate 6 by generating an electrostatic force between the individual electrode 5 and the vibration plate 6 includes an insulation film 7 provided on one or both of opposing surfaces of the fixed electrode and the movable electrode and a surface protection film 8 provided on the insulation film 7. The surface protection film 8 is made of a hard ceramic film or a hard carbon film.