An exposure apparatus includes a stage on which a substrate is placed, a plurality of light irradiation units configured to emit light independently of each other to different positions in a right and left direction on a surface of the substrate, so as to form a strip-like irradiation area extending from one end of the surface of the substrate to the other end of the substrate, a stage moving mechanism configured to move the stage in a back and forth direction relative to the irradiation area, such that the whole surface of the substrate is exposed, and a light receiving unit configured move in the irradiation area between one end and the other end of the irradiation area in order to detect an illuminance distribution of the irradiation area in a longitudinal direction of the irradiation area.