A silicon carbide semiconductor device includes a substrate, a drift layer disposed above the substrate, a base region disposed above the drift layer, a source region disposed above the base region, a gate trench formed deeper than the base region from a surface of the source region, a gate insulating film covering an inner wall surface of the gate trench, a gate electrode disposed on the gate insulating film, an interlayer insulating film covering the gate electrode and the gate insulating film and having a contact hole, a source electrode brought in ohmic contact with the source region through the contact hole, and a drain electrode disposed to a rear surface of the substrate. The source region has a lower impurity concentration on a side close to the base region than on a surface side brought in ohmic contact with the source region.