A semiconductor device includes a substrate, a semiconductor device module, and a heat conductor. The semiconductor device module is on the substrate. The semiconductor device module includes an interposer substrate, one or more semiconductor device chips, a covering resin, and a metal film. The one or more semiconductor device chips are on a first surface of the interposer substrate. The covering resin is in contact with the first surface of the interposer substrate and the one or more semiconductor device chips and encloses the one or more semiconductor device chips. The metal film is in contact with the covering resin and covers the covering resin. The heat conductor is in thermal contact with the substrate and the metal film, and has a higher thermal conductivity than the covering resin.