Disclosed herein is a semiconductor device including: a first laminate having a wiring layer formed on a substrate; a second laminate having a wiring layer formed on a substrate, a principal surface of the second laminate being bonded to a principal surface of the first laminate; a functional element disposed in at least one of the first laminate and the second laminate; and an air gap penetrating an interface between the first laminate and the second laminate, the air gap being disposed on an outside of a circuit formation region including the functional element in at least one of the first laminate and the second laminate as viewed from a direction perpendicular to the principal surfaces of the first laminate and the second laminate.