A process for producing a capacitive electromechanical conversion device by bonding together a substrate and a membrane member to form a cavity sealed between the substrate and the membrane member, the process for producing a capacitive electromechanical conversion device comprises the steps of: providing a gas release path penetrating from a bonded interface between the substrate and the membrane member to the outside, and forming the cavity by bonding the membrane member with the substrate with the gas release path provided; the gas release path being provided at a location where the path does not communicate with the cavity.