To facilitate shortening of image printing time of a thermal transfer printer.

Print mechanisms 2 are arranged at an interval along the carrying passage of a sheet P. A thermal head 5 is disposed oppositely to a platen roller 4. The sheet P is fed between the thermal head 5 and the platen roller 4 and an ink ribbon 6 is passed between the thermal head 5 and the sheet P. The print mechanisms 2 print images of yellow, magenta and cyan simultaneously, while superposing, on the sheet P being fed from a feed reel 3. A post- processing mechanism 13 on the downstream side of the print mechanism 2 performs post-processing on the print face of the sheet P.