The invention provides a printing device and a controlling method thereof. The printing apparatus includes a printing unit that prints images on sheets, a sheet processing unit that executes bookbinding processing on sheets on which images have been printed by the printing unit, a stack control unit that stacks, in a stacking unit, bookbinding products on which bookbinding processing has been executed by the sheet processing unit, a setting unit that sets whether or not to activate a stacking limit of bookbinding products to be stacked on the stacking unit by the stack limiting unit, and a control unit that performs control so as to stop stacking in the stacking unit by the stack control unit in accordance with the stacking limit in the case where the stacking limit of bookbinding products has been set to activated by the setting unit.