A semiconductor device includes a semiconductor chip, a substrate having a main surface on which the semiconductor chip is arranged, a resin case which has a storage space therein and a side wall, the side wall having an injection path extending from the storage space to a device exterior, the resin case having a first opening at a bottom side thereof, connecting the storage space to the device exterior, the substrate being disposed on the resin case, at a main surface side of the substrate facing at the bottom side of the resin case, and a sealing material filling the storage space and the injection path.