A tablet filling instrument 1 for dispensing tablets into a vial 9 in accordance with prescription data and discharging the vial 9 filled with the tablets in one of a plurality of outlets 113 designates at least one of the outlets 113 to be a priority outlet 113p and discharges the vial 9 filled with the tablets in the priority outlet 113p when the tablets are to be dispensed in one of the outlets 113 at a time-point within a predetermined time length from a present time-point.