In order to prevent a printing process from clogging by reason of being incapable of discharging a sheet to a discharge destination in the case of duplex printing on a continuous sheet, the number of pages to be printed continuously on the same side of the sheet is decided so that the number of required discharging destinations conforms to the number of available discharge destinations. Then, according to the decision, printing on the same side of the sheet is performed, and the sheet is discharged to the respective discharge destinations.