A printing apparatus according to one aspect of this invention automatically discharges, of sheets remaining on a conveyance path when a sheet being conveyed jams, dischargeable sheets to one of a plurality of sheet retraction units. At this time, the printing apparatus detects the stacked state of sheets discharged to the sheet retraction unit. When the printing apparatus detects that the sheet retraction unit has become a predetermined state, it changes the discharge destination of sheets to be conveyed to the sheet retraction unit, thereby controlling not to further discharge a sheet to that sheet retraction unit. According to this control, when retracting sheets remaining on the conveyance path upon occurrence of a jam in the printing apparatus, occurrence of a new jam can be prevented.