An image forming apparatus includes: a patch-image generating unit that generates a patch image for measuring a color reproduction characteristic and correcting color, the patch image including mixed-color patch sets each including a plurality of patches each formed by overlaying a plurality of color materials so that patches having the same color and the same tone value included in the mixed-color patch sets are arranged away from each other in a circumferential direction of a photosensitive element and a distance between same tone patches, which are two patches having the same color and the same tone value, is close to (N+½) times the length of a period of uneven density which periodically occurs in the circumferential direction of the photosensitive element (N is an integer equal to or greater than 0); and an image forming unit that forms the generated patch image on a recording medium.