An image forming apparatus has a control unit configured to: after an image is formed in a color mode, if an integrated supply amount is larger than or equal to a reference supply amount, cause a supply image with a first amount of developer, otherwise, cause a supply image with a second amount of developer larger that the first amount; and, after an image is formed in the monochrome mode, cause a supply image with a third amount of developer smaller than the first amount, and, to make an interval between recording materials when the supply image with the third amount is formed shorter than an interval between recording materials when the supply image with the first amount or larger is formed.