In one embodiment, a semiconductor device includes a semiconductor substrate having first and second main surfaces, control electrodes disposed in trenches on the first main surface of the semiconductor substrate and extending in a first direction parallel to the first main surface, and control interconnects disposed on the first main surface of the semiconductor substrate and extending in a second direction perpendicular to the first direction. The semiconductor substrate includes a first semiconductor layer of a first conductivity type, second semiconductor layers of a second conductivity type on a surface of the first semiconductor layer on a first main surface side, third semiconductor layers of the first conductivity type disposed on surfaces of the second semiconductor layers on the first main surface side and extending in the second direction, and a fourth semiconductor layer of the second conductivity type on the second main surface of the semiconductor substrate.