To provide a paper sheet treating apparatus which prevents the incorrect sensing of paper sheets and the like due to cutting and holes of paper sheets and the like when only one sensor to sense paper sheets and the like is arranged at the center of conveyance, and to provide an incorrect cutting prevention method.

A delay signal TR03DL1 and a delay signal TR03DL2 are produced from a sense signal TR03. The OR operation of the delay signal TR03DL1 and the delay signal TR03DL2 are conducted, and the delay signal TR03DL in which the cutting, holes and the like have been corrected is produced. Similarly the OR operation of the sense signal PC09F and PC09B is conducted and the sense signal PC09 is produced. When the dark state of the delay signal TR03DL that has been produced by the method until the front of the sense signal PC09 has been sensed (dark) continues for 45 mm or more, it is evaluated that the paper sheets and the like are the paper sheets that have been conveyed from the upstream to the downstream (upstream passage conditions). When this method is adopted, the incorrect recognition of the paper sheets and the like do not occur even if the paper sheets and the like have cutting and holes.