To prevent the flatness of an exposure surface at the time of setting a film unit at an exposure aperture from being deteriorated due to the inclination of the film unit caused when it is preserved in a film pack over a long term.

Plural film units are housed inside the film pack. Nearly circular-arc-shaped straightening ribs 25 for straightening the inclination of the film unit are respectively formed on the internal walls of two sides in parallel with the ejection direction of the film unit out of four constituting sides in the exposure aperture 18.