A RESURF layer including a plurality of P-type implantation layers having a low concentration of P-type impurity is formed adjacent to an active region. The RESURF layer includes a first RESURF layer, a second RESURF layer, a third RESURF layer, a fourth RESURF layer, and a fifth RESURF layer that are arranged sequentially from the P-type base side so as to surround the P-type base. The second RESURF layer is configured with small regions having an implantation amount equal to that of the first RESURF layer and small regions having an implantation amount equal to that of the third RESURF layer being alternately arranged in multiple. The fourth RESURF layer is configured with small regions having an implantation amount equal to that of the third RESURF layer and small regions having an implantation amount equal to that of the fifth RESURF layer being alternately arranged in multiple.