There is provided an electrostatic actuator with the interdigitated electrode structure comprising a movable rod 11 disposed in parallel with an alignment axis line Ox predetermined on a substrate; a movable interdigitated electrode 12 fixed on the both sides of a coupling point 11 C on the movable rod 11 and having a plurality of movable electrode fingers 12 b; fixed interdigitated electrodes 21, 22 fixed to the substrate and having a plurality of fixed electrode fingers 21 b, 22 b; and four hinges 23, 24 whose one ends are anchored respectively to the movable rod and the other ends are anchored to anchoring points 32 A- 32 D of the substrate. Lengths of those hinges are longer than distances from anchoring points to the alignment axis line and a displacement Lc of a coupling point 11 C in a direction orthogonal to the alignment axis line is reduced to be smaller than a distance between the respective movable electrode fingers and the closest fixed electrode finger.