A semiconductor device and a manufacturing method of the semiconductor device by which peeling off of a sealing resin and a wire from each other can be practically suppressed are disclosed. The semiconductor device includes a substrate, a main face wire, a semiconductor element that is conductive to the main face wire, a sealing resin having resin side faces directed in a direction crossing a thickness direction, the sealing resin sealing the main face wire and the semiconductor element, a through-wire that is conductive to the main face wire and having an exposed rear face exposed from the substrate, and a column conductor that is conductive to the main face wire and having an exposed side face exposed from the resin side faces. The column conductor is supported from the opposite sides thereof in the thickness direction by the substrate and the sealing resin.