According to one embodiment, a semiconductor device includes first to third electrodes, first to fifth layers, and an insulating portion. A position of the third electrode is between a position of the first electrode and a position of the second electrode. The first layer includes first to fifth partial regions. The first partial region is between the fourth and third partial regions. The second partial region is between the third and fifth partial regions. The second layer includes first and second semiconductor regions. The third layer is provided between the third partial region and the third electrode. The fourth layer is provided between the third partial region and the third layer. The fifth layer includes first and second intermediate regions. The third layer is provided between the first and second intermediate regions. The insulating portion includes a first insulating region provided between the third layer and the third electrode.