The invention provides an actuator and an electronic device using the same. In the actuator the effect of the warpage of the beams is reduced and thereby the maximum voltage-capacitance is large and the precipitous change of capacitance in the vicinity of the maximum capacitance is relaxed. The invention provides the actuator comprising a first beam, a first fixed part, a second beam, a first connective part, and a first fixed electrode. The first beam extends from a first fixed end to a first connective end, and the first fixed part connects the first fixed end and the substrate and supportsthe first beam above a main surface of the substrate with a gap. The second beam extends from a second connective end to a first action end and is provided in parallel to the first beam, and has a first division part divided by a first slit extending from the first action end toward the second connective end. The first connective part connects the first connective end and the second connective end and holds the second beam above the main surface of the substrate with a gap. The first fixed electrode is provided on the main surface of the substrate being configured to be opposed to a part of the first division part on a side of the first action end.