A semiconductor device has transistor portions and diode portions. The transistor portions have a semiconductor substrate of a first conductivity type, a first semiconductor region of a second conductivity type, second semiconductor regions of the first conductivity type, gate insulating films, gate electrodes, a first semiconductor layer of the first conductivity type, a third semiconductor region of the second conductivity type, a first electrode, and a second electrode. The diode portions have the semiconductor substrate, the first semiconductor region, the first semiconductor layer, a fourth semiconductor region of the first conductivity type, the first electrode, and the second electrode. The first semiconductor layer has a predetermined region, a depth of the predetermined region from a second main surface of the semiconductor substrate is greater than a depth of a region of the first semiconductor layer excluding the predetermined region, from the second main surface of the semiconductor substrate.