Abstract: Disclosed in the disclosure are a method and apparatus for calibrating an exposure surface of an optical system, and a computer device and a storage medium. The method includes: performing flat-field correction on a photographing module; acquiring a grayscale distribution image; segmenting the grayscale distribution image into a mesh image including a plurality of segmented regions, and calculating a fitting grayscale value of each segmented region; selecting, as a reference grayscale value, a minimum fitting grayscale value from all the fitting grayscale values obtained through calculation, and calculating grayscale compensation coefficients corresponding to the other segmented regions, so as to generate a digital mask; and performing mask compensation, by using the digital mask, on a light projection image projected by the optical system, so as to obtain a printed image of which the exposure surface has a uniform irradiance value.