An extreme ultraviolet light generating apparatus includes a target supply unit configured to output a target toward a predetermined region, a laser system configured to output a first laser beam with which the target is irradiated, a second laser beam with which the target is irradiated after being irradiated with the first laser beam, and a third laser beam with which the target is irradiated after being irradiated with the second laser beam, and an optical system configured to cause an irradiation beam diameter of the second laser beam at the target to be larger than an irradiation beam diameter of the third laser beam at the target.