The present invention is intended to obtain a semiconductor device that is reduced in size, weight, and cost and improved in performance stability and productivity.The semiconductor device includes a semiconductor module in which a semiconductor element is sealed with a resin, a reinforcing beam fixed to an upper surface of the semiconductor module via a plate-like spring, and a frame part to which both ends of the reinforcing beam are fixed, the frame part being disposed in such a fashion as to enclose from four directions an outer periphery of the semiconductor module, plate-like spring, and the reinforcing beam.