An alignment apparatus for aligning a reflective reticle includes a light source for emitting alignment light; an optical unit for guiding the alignment light, which has been emitted by the light source, to an alignment mark provided on the reticle and a reference mark provided on a reticle stage that holds the reticle; and detecting unit for detecting the alignment light reflected from the alignment mark and the reference mark, wherein the reticle is aligned on the basis of the result of detection by the detection unit.