A printing apparatus performs printing with the use of sheets of paper set in any of a plurality of paper-feeding units. The print apparatus is controlled by a method including: determining whether the amount of sheets of paper remaining in a first paper-feeding unit has reached a predetermined amount; and if so switching from the first paper-feeding unit to a second paper-feeding unit. If it is determined that the amount of sheets of paper that remain in the first paper-feeding unit has reached the predetermined amount, control is performed so that the paper-feeding unit that is used for printing should be changed after the ejection of the last one of a plurality of sheets of paper that are included in one set thereof set in the first paper-feeding unit.