An image forming apparatus includes a scanning unit that deflects and scans a laser beam emitted from a laser beam source, an optical system that guides the laser beam onto a photoconductive drum, a storing unit that stores plural correction patterns that give a series of correction values for correcting an amount of laser beams in one scanning, a selecting unit that selects a correction group including at least two kinds of correction patterns out of the stored correction patterns, a switching unit that switches the at least two kinds of correction patterns belonging to the selected group at predetermined timing, a correcting unit that corrects, on the basis of the correction patterns switched by the switching unit, an amount of laser beams being scanned, and a printing unit that prints, on one medium, plural images formed on the photoconductive drum by laser beams corrected by the respective correction patterns.