A semiconductor device has a first board (10) having a first electrically conducting layer (11) and a first electronic element (12) that is provided on the first electrically conducting layer (11); and an intermediate layer (20) being provided on the first board (10), and having a plurality of connectors and a resin board section, in which the plurality of connectors are fixed. The connector is exposed from the resin board section on the first board (10) side, and connected with the first electrically conducting layer (11) or the first electronic element (12).