A semiconductor device includes a semiconductor substrate including a first surface and a second surface opposite to the first surface, and a through-via penetrating the semiconductor substrate. The through-via has a stacked structure of a first conductive film formed in a portion of the semiconductor substrate closer to the first surface, and a second conductive film formed in a portion of the semiconductor substrate closer to the second surface. An insulating layer is buried inside the semiconductor substrate. The first conductive film is electrically connected to the second conductive film in the insulating layer.