An image forming apparatus includes: a document feed section; a document reading section; a discharged document sensor detecting the discharged document already read by the document reading section; an image storage section storing a document image obtained through the reading by the document reading section; an image formation section performing an image formation operation in which a toner image of the document image is formed on paper; a fixing section performing fixing processing of heating and pressurizing the paper on which the image has been formed to fix the toner image on the paper; and a control section, upon judgment, with reference to a signal of the discharged document sensor before image formation of a predefined number of pages of document images stored in the image storage section, that the discharged document exists, stopping the image formation of the predefined number of pages of document images.