An object of the invention is to provide a smaller semiconductor device of which the manufacturing process is simplified and the manufacturing cost is reduced and a method of manufacturing the same. Furthermore, an object of the invention is to provide a semiconductor device having a cavity. A first supporting body 5 having a penetration hole 6 penetrating it from the front surface to the back surface is attached to a front surface of a semiconductor substrate 2 with an adhesive layer 4 being interposed therebetween. A device element 1 and wiring layers 3 are formed on the front surface of the semiconductor substrate 2. A second supporting body 7 is attached to the first supporting body 5 with an adhesive layer 8 being interposed therebetween so as to cover the penetration hole 6. The device element 1 is sealed in a cavity 9 surrounded by the semiconductor substrate 2, the first supporting body 5 and the second supporting body 7.