To provide a diaphragm capable of generating a large displacement without complicating its structure and to structure an element of a microactuator having a large displacement by using the diaphragm.

A large deflection is generated and a large displacement is obtained by making a flexible part of a minute diaphragm in a fine hollow structured shape. By making the shape of the fine hollow structure annular, or a fine double hollow structured shape comprising the fine hollow structure at the center and an annular fine hollow structure surrounding the fine hollow structure at the center, the displacement of the fine diaphragm can be enhanced. By structuring the flexible part of the fine hollow structure by a metallic glass film, an elastic deformation range can be made large, and the diaphragm can be manufactured without complicating the process too much.