Formed on the surface of an n-type semiconductor layer (21) taken as a collector region is a base region (22) consisting of a p-type region, and formed in the p-type region is an emitter region (23) consisting of an n+-type region. Further, provided in the base region is a base electrode connecting portion (24) consisting of an n+-type region, and a base electrode (26) is connected to the surface of the base electrode connecting portion, and an emitter electrode (27) and a collector electrode (28) are provided and connected electrically to the emitter region and the collector region (21), respectively. As a result, a semiconductor device is obtained which has the transistor in which the reduction in power consumption with a high withstand voltage can be achieved, and the fast switching speed is possible and the large current is obtained. Further a voltage-drive type bipolar transistor such as a digital transistor is obtained which is small in load capacity while establishing a desired drive voltage.