A semiconductor device, comprising: a semiconductor element; a support substrate (1); an insulating material layer (4) for sealing the semiconductor element (2a, 2b) and a periphery thereof; a metal thin film wiring layer provided in the insulating material layer (4), with a part thereof being exposed on an external surface; and metal vias (9) provided in the insulating material layer (4) and electrically connected to the metal thin film wiring layer, wherein the semiconductor element (2a, 2b) is provided in a plurality, and the respective semiconductor elements (2a, 2b) are stacked via an insulating material (4) such that a circuit surface of each semiconductor element (2a, 2b) faces the metal thin film wiring layer, and electrode pads of each semiconductor element (2a) are exposed without being hidden by the semiconductor element (2b) stacked thereabove, and electrically connected to the metal thin film wiring layer. The semiconductor device can be manufactured in a smaller and thinner size and the number of manufacturing steps can be reduced by causing a plurality of semiconductor chips to be a vertically-stacked structure.