An image forming apparatus includes a conveyance section, an image forming section, a fixing section, a sheet output tray, a toner container, a suitable product determining section, and a control section. The suitable product determining section determines whether the toner container loaded in an apparatus body is a suitable product. When the suitable product determining section determines that the toner container is not a suitable product, the control section allows the conveyance section, the image forming section, and the fixing section to form, on a sheet, a solid image having a circumferential length of one of rotating bodies of the fixing section or longer, and allows the sheet on which the solid image is formed to pass through a fixing nip, to thereby periodically allow a cleaning operation of removing a contamination adhering to surfaces of rotating bodies of the fixing section to be performed.