To prevent easy loading of a used cartridge with a photographic film.

A photographic film to be housed in a cartridge is locked at its end on a winding core 5. The core 5 is provided with a film locking chamber 19 having a locking pawl 20 and a pressing pawl 21. The film locking chamber 19 is provided with a meandering film insertion slot 13. When a photographic film is to be inserted into the film insertion slot 13, it is required to bend the photographic film in the width direction, and this means that a photographic film inserted from the outside of the cartridge can not be locked on the winding core and that a cartridge once used can not be re-loaded with a photographic film.