To prompt the release of jam from the side of a large-amount paper feed device 10 when a print paper sheet is stayed at this side of an inlet of a printer 20, in a print system having the printer 20 and the large-amount paper sheet feed device 10 (pre-processing device).

A printer 20 comprises a virtual jam information output part 44 for outputting virtual jam information to a large-amount paper sheet feed device 10 when it is detected that the whole or a portion of the print paper sheet P sent out from the large-amount paper sheet feed device 10 does not arrive at the printer 20, and the large-amount paper sheet feed device 10 comprises a virtual jam recognition part 16 which receives the virtual jam information, and recognizes the case that the jam of the print paper sheet P not arriving at the printer 20 is not detected in the large-amount paper sheet feed device 10 as the occurrence of virtual jam.