In a manufacturing method of a semiconductor device, a semiconductor chip is sealed with a resin, and then a laser is applied to remove the resin so that a part of the semiconductor chip is exposed. The semiconductor chip is made of a material that has a lower absorptivity of the laser than the resin and is not melted by the laser. The laser has a wavelength that passes through the semiconductor chip and has a lower absorptivity in the semiconductor chip than in the resin. The laser is applied to the resin from a side adjacent to one of plate surfaces of the semiconductor chip, so that the resin sealing the one of the plate surfaces is sublimated and removed and at least a part of the resin sealing the other of the plate surfaces is subsequently sublimated and removed by the laser having passed through the semiconductor chip.