An image forming apparatus is provided with: an image forming unit that forms an image on a medium according an image forming condition; a speed changing unit that changes an image forming speed of the image forming unit between a plurality of image forming speeds including a first image forming speed; an adjusting unit that adjusts the image forming condition set in the image forming unit; a measuring unit that measures an elapsed state after the image forming condition is adjusted for the last time at the first image forming speed in the image forming unit, and outputs a measured value indicative of the elapsed state; and a determination unit that determines, according to the elapsed state, whether or not to adjust the image forming condition before the image forming unit starts forming an image at the first image forming speed.