A semiconductor device includes: a semiconductor element; a support as a metallic member that includes a metallized layer having a first component as an iron group element and a second component as a periodic table group five or group six transition metal element other than chromium provided at an outermost surface of the support, and is arranged such that the outermost surface faces the semiconductor element; a joint material that is arranged between the outermost surface of the support and the semiconductor element, and is joined with the outermost surface to fix the semiconductor element to the support; and a molding resin that is arranged to cover a joint body having the support, the joint material and the semiconductor element.