A living body feature input device comprising a one-dimensional or quasi-one-dimensionalimage sensor. When a finger and the image sensor slide relatively, a finger travelguide guides the finger not to touch the effective pixel part of the image sensorbut to keep a substantially constant distance between them. An image processingsection joins an image of light scattered in the finger and radiated from the skinsurface of the finger to a one-dimensional or quasi-one-dimensional partialimage picked up by the image sensor during relative sliding.
