A ribbon advance mechanism has a advancing spool, a metal support shaft for supporting a advancing spool base part for rotation, and a coil spring attached between a base part of the advancing spool and the support shaft. The coil spring is mounted on a center part of the support shaft in a state in which it is slightly spread. One end part of a hook of the coil spring is fixed to a slit of the advancing spool base part, whereby the advancing spool is allowed to rotate only in an advancing direction (R direction), and when power is not transferred to the advancing spool, an ink ribbon is not slack. The coil spring is placed in a enclosed space by the base part of the advancing spool and a base part of the support shaft.