A hook of a cartridge-chamber lid is engaged with one end of an engagement lever to be kept in a closed position. The other end of the engagement lever is engaged with an intermediate lever attached to an upper face of a cartridge chamber. When a photo film is wound up, a winding-up lock mechanism comprising an urging gear, a lever member and a winding-up lock member prevents the intermediate lever from rotating, namely prevents the engagement lever from swinging to lock the cartridge-chamber lid. When the photo film is rewound, a rewinding lock mechanism comprising an urging gear, a lever member, a rewinding lock member and a torsion spring prevents the intermediate lever from rotating, namely prevents the engagement lever from swinging to lock the cartridge-chamber lid.