An extreme ultraviolet (EUV) light generator includes a collecting mirror having a first focal point and a second focal point, the first focal point being closer to the collecting mirror than the second focal point, a laser to generate a laser beam and to radiate the laser beam toward the first focal point of the collecting mirror, and a droplet generator to generate a droplet and to discharge the droplet at the first focal point of the collecting mirror, wherein the collecting mirror includes a concave reflective surface, a through hole in a center of the reflective surface, and a drip hole between the through hole and an outer circumferential surface of the reflective surface.