A sheet film package includes a tray for storing a stack of sheet films and a flexible cover member peelably attached to the tray in covering relation to a film access opening for shielding the sheet films in the tray from extraneous light. The cover member is folded back on itself at one end of the tray and has an end portion which extends over the other end of the tray and which will be exposed from a loading device when the sheet film package is loaded in the loading device. The sheet film package may have a cushioning member disposed in the tray and composed of hollow air bags of a flexible material for pressing the holding the sheet films in the package member. A film loading device for loading the sheet film package therein include a light-shielding member for preventing extraneous light from entering a loading slot. The loading slot is closed by a pivotally mounted cover with the end portion of the cover member being led out of the loading slot. The light-shielding member may comprise a roller for pressing the cover member against an engaging portion of the sheet film package or the cover, or may comprise light-shielding blocks mounted on the cover and a frame of the device, respectively, for gripping the cover member therebetween.