A banknote processing device includes a first pay-out port and a second pay-out port in which banknotes for pay-out are stacked, a conveyance section that conveys banknotes to the first pay-out port or to the second pay-out port, a first opening-closing member capable of opening and closing the first pay-out port by moving, a second opening-closing member capable of opening and closing the second pay-out port by moving, and a controller that controls conveyance of the banknotes by the conveyance section, and that controls opening and closing operations of the first and second opening-closing members. When the number of banknotes stacked in the first pay-out port has reached a maximum stacking number in pay-out processing, the controller performs a switching operation to switch a conveyance destination of the banknotes from the first pay-out port to the second pay-out port, and performs an opening operation to open the first opening-closing member.