According to one embodiment, a semiconductor device includes a first semiconductor region, a second semiconductor region, a third semiconductor region, an insulating film, and a control electrode. The first semiconductor region includes a silicon carbide of a first conductivity type. The second semiconductor region is provided on the first semiconductor region, includes a silicon carbide of a second conductivity type, and has a first main surface. The third semiconductor region is provided on the second semiconductor region and includes the silicon carbide of the first conductivity type. The film is provided on the surface. The electrode is provided on the film, and has a first region close to the third semiconductor region side, and a second region closer to the first semiconductor region side than the first region. An effective work function of the first region is larger than an effective work function of the second region.