To improve operability at the time of manually pushing a medium in a medium processing unit, or pulling the medium out of the medium processing unit.

A medium insertion port 8 is always closed by a shutter 20, and the shutter 20 is pushed up by a card 30 inserted from the medium insertion port 8, and the medium insertion port 8 is opened. The card 30 inserted from the medium insertion port 8 is inserted and pushed in a card processing unit 12 so that the terminal of the card 30 can be electrically connected to the contact pin of the unit 12. The shutter 20 is mounted on the excessive edge of a plate spring 15 whose base edge side is mounted on a print wiring board 10, and energized in a direction where the medium insertion port 8 is closed by the plate spring 15. The front edge of the card 30 is abutted on first and second ribs 25 and 26 as inclined sections formed in the shutter 20 so that a partial output in a direction where the medium insertion port 8 is closed can be generated in the shutter 20.