A technique for reducing downtime that accompanies the execution independently of adjustment processing for maintaining image quality and the execution of finishing processing relating to a printing medium. In order to apply the finishing processing to the printing medium in a finishing processing unit, an image forming apparatus to which this technique is applied sets a time between sheets that extends from end of image formation regarding a first sheet of the printing medium to start of image formation regarding a second sheet of the printing medium transported following the first sheet of the printing medium in the image forming unit, and executes adjustment processing, which is for maintaining image quality in the image forming unit, within the set time between sheets.