Provided is a method of manufacturing a semiconductor device capable of adhering semiconductor elements and a support member for mounting semiconductor elements, such as lead frames, organic substrates or the like, even in a relatively low temperature range without damaging adhesion property and workability and of suppressing the occurrence of voids. The method of manufacturing a semiconductor device according to the invention is a method of manufacturing a semiconductor device comprising a semiconductor element and a support member adhered to the semiconductor element through a cured material of an adhesive film, wherein the method comprises the steps (a) to (d) in this order; (a) preparing adhesive film-attached semiconductor elements; (b) thermocompression-bonding said adhesive film-attached semiconductor elements to said support member so as to obtain a semiconductor part made of said adhesive film-attached semiconductor elements and said support member; (c) heating and pressurizing said semiconductor part made of said adhesive film-attached semiconductor elements and said support member using a pressurized fluid so as to proceed with curing of adhesive film; and (d) electrically connecting said adhesive film-attached semiconductor elements and said support member.