A semiconductor device includes an IGBT region extending from a front surface to a rear surface of a semiconductor substrate including a first conductive type drift layer, and a diode region lying adjacent to the IGBT region. The IGBT region includes a second conductive type base layer on a side facing the front surface and a first trench portion penetrating the base layer. The first trench portion includes a first gate electrode, a second gate electrode provided directly below the first gate electrode, and an insulating film provided on a side surface of the first gate electrode, between the first gate electrode and the second gate electrode and in a position to contact the second gate electrode. The diode region includes a second conductive type anode layer and a second trench portion including a dummy gate electrode on the side facing the front surface.