Semiconductor device and method of manufacturing semiconductor device

There is provided a semiconductor device in which the inter-wiring capacitance of wiring lines provided in any layout is further reduced. A semiconductor device (1) including: a first inter-wiring insulating layer (120) that is provided on a substrate (100) and includes a recess on a side opposite to the substrate; a first wiring layer (130) that is provided inside the recess in the first inter-wiring insulating layer; a sealing film (140) that is provided along an uneven shape of the first wiring layer and the first inter-wiring insulating layer; a second inter-wiring insulating layer (220) that is provided on the first inter-wiring insulating layer to cover the recess; and a gap (150) that is provided between the second inter-wiring insulating layer and the first wiring layer and the first inter-wiring insulating layer. The second inter-wiring insulating layer has a planarized surface that is opposed to the recess.