To provide a paper sheet processor adapted to recognize an identification code assigned to a cassette storing paper sheets processed by the paper sheet processor, whereby the cassette can be taken out and installed to the paper sheet processor to process the internal paper sheets.

In separation of paper sheets stored in a cassette 57D to normal slip and impaired slip, when an operator installs the cassette 57D to a cassette feed table 71 and starts the device, the bar code 57F of the cassette 57D is read by a bar code reader 72 to read the kind of slip and the number of slips from a storage part. At the same time, the cassette 57D is unlocked, and the paper sheets in the cassette are pushed out by a backup plate 57E, transferred to the feed table 70, pressed onto a pickup roller 5 side by a backup plate 4A, taken out one by one by a take-out roller 30, discriminated by a paper sheet discrimination device 19, and separately stored in designated cassettes for normal slip and impaired slip.