An exposure method which has a step of offsetting a first scanning line bend by scanning means with a second scanning line bend by an image forming lens, and/or a step of correcting angles of optical axis of a plurality of light beams in accordance with the amount of a deviation in a subscanning direction due to a difference of the angles of incidence, so that a distance between scanning lines on a photosensitive body due to the plurality of light beams is corrected. An image forming apparatus which has an image forming lens for producing a second scanning line bend is so as to offset a first scanning line bend by scanning means, and/or correcting means for correcting angles of optical axis of a plurality of light beams in accordance with the amount of a deviation in a subscanning direction due to a difference of the angles of incidence, so that a distance between scanning lines on a photosensitive body due to the plurality of light beams is corrected.