Provided is an HEMT exhibiting a normally-off characteristic and low on-state resistance, which includes a first carrier transport layer; two separate second carrier transport layers formed of undoped GaN and provided on two separate regions of the first carrier transport layer; and carrier supply layers formed of AlGaN and respectively provided on the two separate second carrier transport layers. The second carrier transport layers and the carrier supply layers are respectively formed through crystal growth on the first carrier transport layer. The heterojunction interface between the second carrier transport layer and the carrier supply layer exhibits high flatness, and virtually no growth-associated impurities are incorporated in the vicinity of the heterojunction interface. Therefore, reduction in mobility of 2DEG is prevented, and on-state resistance is reduced.