A method of manufacturing a semiconductor device and a semiconductor device that is manufactured by the method. In the method of manufacturing a semiconductor device, a releasing sheet is disposed in close contact with a hole of an aluminum plate having the recessed hole, and a skeleton structure of a semiconductor device is put into the recessed hole. Then, liquid epoxy resin is poured into the recessed hole. After hardening, the epoxy resin body 10 including the skeleton structure is taken out from the recessed hole to complete manufacturing the semiconductor device. Using a simple molding jig including the aluminum plate, and covering the skeleton structure with the epoxy resin body, a highly reliable semiconductor device with a case-less construction can be manufactured.