Abstract: There is provided a tablet printing apparatus that can perform printing at a high speed on tablets arbitrarily supplied in volume at irregular intervals and has a high printing quality. A tablet printing apparatus 1 for multicolor printing on tablets T comprises a conveying belt 24 for conveying the tablets T in a moving direction A1-A2, an inkjet printer 42 disposed in the middle of the moving direction A1-A2 of the conveying belt 24 for performing non-contact printing onto surfaces of the tablets T conveyed by the conveying belt 24, an encoder 28 and a tablet sensor 29 for detecting moving positions of the tablets T conveyed by the conveying belt 24, and a unit control substrate 32 for controlling printing timing on the tablets T of the inject printer 42 or 46 based on the moving conditions or/and the moving positions of the tablets T detected by the encoder 28 and the tablet sensor 29.