1. A biometrical feature inputting system comprising: an imager placed in front of a finger, for imaging an image of a front face of said finger, and an image of either one of lateral faces of said finger; a reflector placed on at least one side of lateral faces of said figure, for reflecting an image of lateral faces of said finger to said imager; and a synthesizer for applying mirror inversion to an imaged image of lateral faces of said finger, and synthesizing a mirror-inverted image of lateral faces of said finger and an imaged image of a front face of said finger.