To provide a transporting system of roll ink ribbon in which elongation of print can be minimized by varying a drive torque being applied to a shaft depending on the roll diameter of a roll ink ribbon (thermal ink ribbon 18) such that the tension falls within an appropriate range.

In order to reduce elongation of print by varying a torque being applied to a ribbon holding shaft 19 or a ribbon winding shaft 26 depending on the roll diameter of an ink ribbon 18 and minimizing an actual tension being applied to the ink ribbon 18, a mechanism 42 for detecting the roll diameter of the ink ribbon 18 and torque varying mechanisms 48 and 49 each comprising an electromagnetic clutch for braking at least any one of feeding action from a ribbon holding mechanism 13 or winding action to a ribbon winding mechanism 14 depending on the roll diameter detected by the roll diameter detecting mechanism 42 are provided.