To enable easy adaption to a high-density arrangement and to obtain an efficient fluid ejecting characteristic even in the case of a high-density arrangement.

In the functional element which includes a plurality of diaphragms 11, each supporting part 17a for supporting each diaphragm 11 to be deformable, and a paired electrode for applying a pressure change to a fluid by deforming each diaphragm 11 by a static electricity or for detecting an electrostatic capacity by deforming the diaphragm 11 through a pressure change of the fluid, each supporting part 11 is arranged into an annular shape.