To provide a thermal transfer apparatus for cards which can detect the near end of a transfer medium without changing the transfer medium.

A middle transferring thermal transfer printer 1 is equipped with a winding roller 53 for winding an ink ribbon and conveying it, a search sensor 57 for detecting the search mark on the ink ribbon and a judgement section 67 for measuring the elapse time until detecting the next search mark after the search sensor 57 detects the search mark when the ink ribbon is conveyed and judging that the residual quantity of the ink ribbon is very small when the elapse time is shorter than a specified time.