To provide an ink ribbon cassette which erases a print mark without bringing a load to be borne upon an ink ribbon by widening the transfer range of a transfer part.

A rotary transfer part 1 is provided on the ink ribbon 4 side and the ink ribbon 4 is pinched between an erasing head 2 and the transfer part 1 which rotates synchronized with a take-up bobbin 5. The ink ribbon 4 has a left print mark erased by the erasing head 2 after the use for printing by a printing head 2 and thus the secrecy leak by the ink ribbon 4 is prevented from occurring.