The semiconductor device includes a semiconductor module and a cooler. The semiconductor module includes an insulator substrate, an inner conductor film disposed on a first surface of the insulator substrate, a semiconductor element connected to the inner conductor film, a sealing body sealing the inner conductor film and the semiconductor element, and an outer conductor film disposed on a second surface of the insulator substrate and exposed from a surface of the sealing body. The cooler is disposed adjacent to the outer conductor film via a thermal interface material having fluidity. The outer conductor film has a protruding portion or a recessed portion on a surface being in contact with the thermal interface material.