An image forming apparatus includes an image carrier, a developing part, a storing part and an adjusting part. The image carrier includes a surface. An electrostatic latent image formed on the surface is developed by a toner, and then, a toner image is formed on the surface. The developing part contains the toner supplied from a toner cartridge and supplies the toner to the image carrier. The storing part stores information relating to a replacement rate when a first toner in the developing part is replaced by a second toner, in a case where kinds of the first toner contained in the developing part and the second toner being supplied from the toner cartridge are different. The adjusting part adjusts density of the toner image on the basis of the replacement rate when a toner cartridge containing the first toner is replaced by another toner cartridge containing the second toner.