An image forming apparatus, including an image former forming a toner image on an image bearer; a transferer transferring the toner image onto a recoding medium; a cleaner collecting a waste toner remaining on an image bearer after transferred; a waste toner collection container accumulating the waste toner therein; a detector detecting whether the container is properly set in the image forming apparatus; and another detector detecting that the container is nearly full of the waste toner, wherein the image forming apparatus further comprises a determiner determining a quantity of the waste toner in the container; another determiner determining whether the container is properly exchanged with a vacant container; and a limiter limiting a printable quantity after the container is detected to be nearly full of the waste toner, based on the another determiner.