A countercurrent tank type supercritical water reactor with a sacrificial lining, comprising a cylinder body and a catalyst tank arranged inside, the upper part of the cylinder body is connected with a top cover, and the lower part of the cylinder body is connected with a spherical head, the inner side of the cylinder body, the inner side of the spherical head and the inner side of the top cover constitute the inner wall of the reactor, wherein the inner wall of the reactor is provided with a high temperature resistance and thermal insulation coating layer, the inner wall of the high temperature resistance and thermal insulation coating layer is provided with a sealing coating layer, and the inner wall of the sealing coating layer is provided with the sacrificial lining. The reactor is of a countercurrent tank type, which can prevent the reactor blockage caused by salt deposition.