To provide a thermal transfer printer which can prevent liquid dripping and liquid leakage of a solvent for erasing a recording mark left on an ink ribbon.

The thermal transfer printer, which thermally transfers an ink of the ink ribbon to a recording paper and erases the recording mark left on the ink ribbon by bringing a contact means impregnated with a treatment liquid into contact with the ink ribbon, further includes a storage container which stores the treatment liquid, and a supply member which supplies the treatment liquid from the storage container to the contact means. The supply member supplies the treatment liquid of the storage container to the contact means by using the capillary phenomenon caused by immersing one end into the storage container and bringing the other end into contact with the contact means.