According to one embodiment, a semiconductor device includes a first semiconductor layer of a first conductivity type, a second semiconductor layer, a third semiconductor layer, a fourth semiconductor layer, first trenches, a second trench, an insulating film, a gate electrode, a first main electrode, a second main electrode, a channel stopper layer and a channel stopper electrode. The second semiconductor layer of the first conductivity type is provided on the first semiconductor layer. The third semiconductor layer of a second conductivity type is provided on the second semiconductor layer. The fourth semiconductor layer of the first conductivity type is provided on the third semiconductor layer. The gate electrode is provided in the first trenches via the insulating film. The first main electrode is provided on the first semiconductor layer. The second main electrode is provided to contact the element part. The channel stopper electrode is provided on the termination part.