A semiconductor device includes a semiconductor module. The semiconductor module includes a package made of resin. The package contains a semiconductor element and a heat sink. The heat sink has a thermal conductive surface exposed on a part of one surface of the package. The semiconductor device includes an insulating plate, which is a part of a cooler, facing the thermal conductive surface of the heat sink and a resin surface around the thermal conductive surface, and pressed against the semiconductor module. At least a part of the thermal conductive surface comprises a recessed region recessed with respect to the resin surface. A solid heat transfer layer is interposed between the recessed region of the thermal conductive surface and the insulating plate, and is not interposed between the resin surface and the insulating plate.