In connection with a printer, a platen roller is configured to transport a recording medium. A print head has a head body portion having a printing portion which performs printing on a recording medium and facing the platen roller. A supporting mechanism supports the head body portion, presses the head body portion against the platen roller and moves the head body portion by rotation of the platen roller. When the platen roller rotates in a second direction opposite the first direction, a contact position of the head body portion with respect to the platen roller is shifted while maintaining the head body portion pressed against the platen roller.