A thermal printer includes heating elements each of which generates heat according to an amount of energy applied thereto, an energy applier that applies energy to each of the heating elements, a memory that stores a gradation table where energy values are set for gradation levels based on a relationship between reflectances of a printed image and amounts of energy applied to the heating elements, and a controller that transfers control data corresponding to gradation levels of image data to the energy applier based on the gradation table to control the amounts of energy to be applied by the energy applier to each of the heating elements.