A silicon carbide semiconductor device includes a semiconductor substrate containing silicon carbide, a semiconductor layer formed over the semiconductor substrate, and a plurality of well regions formed on a front surface side of a cell forming area set to the semiconductor layer. The device further includes source layers formed on the front surface side lying within the well regions, an outer peripheral insulating film thick in thickness, which is formed over the semiconductor layer in an outer peripheral area surrounding the cell forming area, a gate oxide film formed over the front surface of the semiconductor layer in the cell forming area, and a gate electrode layer formed so as to extend from above the gate oxide film to above the outer peripheral insulating film.