Semiconductor device manufacturing method

There is provided a semiconductor device manufacturing method and semiconductor device (10) such that it is possible to reduce the manufacturing cost of a semiconductor device (10) wherein a resin case (15) and terminal (17) are provided integrally. A semiconductor device (10) includes a resin case (15) in which are provided a plurality of terminals (17) having a leg portion (17a). When manufacturing the resin case (15), a molding die (20) in which are provided protrusions (21a) that fix each of the plurality of terminals (17) in a predetermined position is used as the molding die (20) for molding the resin case (15). Each of the plurality of terminals (17) is matched with and held by the corresponding protrusions (21a) in the molding die (20), and resin is injected into the molding die (20), thus integrally molding the plurality of terminals (17) and the resin case (15).