A plurality of semiconductor chips, a module substrate on which the plurality of semiconductor chips are mounted, a heat sink on which the module substrate is mounted, and a filler filled between the module substrate and the heat sink are included, in which the module substrate includes a heat radiating plate, and an insulating substrate on which the plurality of semiconductor chips are mounted, the heat radiating plate has a plurality of recess portions provided on a surface facing the heat sink and at least one groove, the plurality of recess portions are provided in regions corresponding to below arrangement regions of the plurality of semiconductor chips, the at least one groove is provided in a region corresponding to below a region between at least one of the plurality of semiconductor chips and an adjacent other semiconductor chip, and the filler also is filled in the plurality of recess portions.