Abstract: A copying device according to the present invention includes a manuscript supply unit for supplying the manuscripts to be copied in an automatic or a semi-automatic fashion, a two-sided and a multiple copying mechanisms that supply the copying papers again to the image copying unit, for carrying out a two-sided copying and a multiple copying, a detection device which detects the number of sheets of the manuscripts to carry out a two-sided copying or a multiple copying, and a microcomputer that is programmed so as to forbid the copying operation when the number of sheets of the copying papers to be collected in a temporary collecting unit that is determined by multiplying the number of sheets detected by said detecting means with a set number of sheets of copies to be taken, exceeds a predetermined allowed collecting number of sheets in the temporary collecting unit.