A light amount adjustment method for use in an image exposure apparatus records an image by scanning a photosensitive material with a light beam modulated in accordance with image signal. The light beam has a first light amount level and a second light amount level that is higher than the first light amount level to perform exposure of one dot. The method sets the first light amount level based on the image signal, exposes test patches by displacing a focus position of the light beam on the photosensitive material and changing the second light amount level that is outputted in accordance with changing of the image signal and adjusts the second light amount level such that halftone dot percent fluctuations of the exposed test patches are minimized to set the adjusted second light amount level.