The present invention is directed to an MIS type semiconductor device, including a channel layer between a semiconductor body region and a gate insulating film, the channel layer having an opposite semiconductor polarity to that of the semiconductor body region. Since Vfb of the semiconductor device is equivalent to or less than a gate rated voltage Vgcc− of the semiconductor device with respect to an OFF-polarity, density of carrier charge that is induced near the surface of the semiconductor body region is kept at a predetermined amount or less with a guaranteed range of operation of the semiconductor device.