Provided is a method of manufacturing a molded product that can reduce problems on a reinforcing plate during pressing. In one aspect of the present disclosure, the method of manufacturing a molded product includes welding a first metal plate overlaid with a second metal plate to the second metal plate; and pressing the first metal plate and the second metal plate together. In the pressing, a base surface and a wall surface are formed on the first metal plate; the wall surface is disposed to cross the base surface. In the welding, a first welding is performed on a reinforcing portion of the second metal plate that is overlaid on an area of the first metal plate that is formed into the wall surface; and subsequently, a second welding is performed in a direction crossing a direction of the first welding.