A lens-fitted photo film unit comprises a main body, a bottom lid, and a photo film. The main body has an exposure chamber with a taking lens. The exposure chamber is provided with a plane mirror disposed in such a manner as to be inclined 45 degrees with respect to the optical axis of the taking lens. Since the plane mirror reflects light from a subject, a photographic optical path of the light is perpendicularly bent. Subject light forms an image on the photo film disposed in parallel with the optical axis. A side print is exposed in the manufacture on the lateral edge of the photo film. Since the orientation of the photographed image is the same as that of the side print, it is possible to easily confirm the orientation of the photographed image in the development and print processes.