According to one embodiment, a tablet printing device (1) includes: a conveyer (3) configured to convey a tablet along a line； an applicator head (5A) including a plurality of nozzles arranged in a direction crossing the conveyance direction of the tablet conveyed by the conveyer, configured to perform printing on the tablet by ejecting a liquid from the nozzles； and a controller (9) configured to control the ejection of the liquid from the nozzles of the applicator head (5A). The length of an array of the nozzles in a direction perpendicular to the conveyance direction is equal to or longer than the length of the tablet in the direction perpendicular to the conveyance direction. The controller (9) is further configured to control switching of switch a nozzle used for printing on the tablet among the nozzles by a plurality of sections determined in advance.
