A laser beam controlling device may include: a guide laser device; a guide laser beam wavefront adjuster provided in a beam path of the guide laser beam outputted from the guide laser device; a beam combiner configured to adjust travel directions of a laser beam outputted from a laser system and the guide laser beam outputted from the guide laser beam wavefront adjuster to coincide with each other, a both beam wavefront adjuster provided in a beam path of both the laser beam and the guide laser beam outputted from the beam combiner, a beam monitor provided in a beam path of both the laser beam and the guide laser beam outputted from the both beam wavefront adjuster, and a controller configured to control the guide laser beam wavefront adjuster and the both beam wavefront adjuster based on detection results at the beam monitor with respect to both the laser beam and the guide laser beam.