A guide member is disposed between a thermal head and a conveyor roller pair. The guide member projects into a conveyance passage of a recording paper when a platen roller is separated from the thermal head. In this state, the guide member abuts on the recording paper having been forwarded by the conveyor roller pair. Further, the guide member guides the recording paper to feed it between the platen roller and the thermal head. When the platen roller is pressed against the thermal head, the guide member is pushed by support plates of the platen roller. The pushed guide member is lowered so that the guide member is evacuated from the conveyance passage of the recording paper.