An image forming apparatus includes: a display portion; an image forming device; a fixing device; a controller configured to control display of the display portion so that one is selected from a plurality of sheet widths to impose a limitation on a use of the image forming apparatus; a storing portion, provided detachably mountable to the image forming apparatus together with the fixing device, configured to store information corresponding to the sheet width selected at the display portion; a reading portion configured to read information stored in the storing portion; and a limiting portion configured to impose, on the basis of the information read by the reading portion, a limitation on widths of sheets capable of being designated as a printing condition.