[Problem to be Solved] Provided is a semiconductor device in which the trade-off between the pressure resistance and the on-state resistance is improved and the performance is improved.[Solution] The semiconductor device 1 of the present invention comprises semiconductor layers 20 to 23, an anode electrode 12, and a cathode electrode 13, wherein the semiconductor layers include a composition change layer 23, the anode electrode 12 is electrically connected to one of principal surfaces of the composition change layer through a formation of a Schottky junction between the anode electrode 12 and a part of the semiconductor layers, the cathode electrode 13 is electrically connected to the other of the principal surfaces of the composition change layer through a formation of a junction between the cathode electrode 13 and another part of the semiconductor layers, the anode electrode 12 and the cathode electrode 13 are capable of applying a voltage to the composition change layer 23 in a direction perpendicular to the principal surface, andthe composition change layer 23 has composition that changes from a cathode electrode 13 side toward an anode electrode 12 side in the direction perpendicular to the principal surface of the composition change layer, has a negative polarization charge that is generated due to the composition that changes, and contains a donor impurity.