According to one embodiment, a semiconductor device includes a first semiconductor region, a second semiconductor region, a third semiconductor region, a fourth semiconductor region, an insulating film, a control electrode, a first electrode, and a second electrode. The first semiconductor region includes silicon carbide, and has a first portion. The second semiconductor region is provided on the first semiconductor region, and includes silicon carbide. The third semiconductor region and the fourth semiconductor region are provided on the second semiconductor region, and includes silicon carbide. The electrode is provided on the film. The second semiconductor region has a first region and a second region. The first region contacts with the third semiconductor region and the fourth semiconductor region. The second region contacts with the first portion. The impurity concentration of the first region is higher than an impurity concentration of the second region.