A laser machining device which can suppress the aberration of a laser beam converged into an object to be machined is provided. The device includes a laser light source for emitting a laser beam and a reflective spatial light modulator for modulating the laser beam emitted from the laser light source (202), while first mirrors for reflecting the laser beam are disposed between the laser light source and reflective spatial light modulator in an optical path of the laser beam and configured such as to be able to adjust the direction of reflection of the laser beam. Therefore, by regulating the direction of reflection of the laser beam at each of the mirrors, the device can adjust the position and incident angle of the laser beam incident on the reflective spatial light modulator as desired. Hence, the laser beam can precisely be made incident on the reflective spatial light modulator.