A vein authentication apparatus according to the present invention is provided with a vein pattern extraction unit for extracting a vein pattern from each of the plurality of vein image data, a rotational amount calculation unit for calculating a rotational direction and an amount of rotation of the finger, a registration information selection unit for calculating a shift width of the imaging range, and for determining whether the shift width of the imaging range is equal to or more than a predetermined threshold value, and for selecting a vein pattern to be registered as a template from among the plurality of vein patterns, and for setting the selected vein pattern as registration information, and a registration information compression unit for compressing, in accordance with the shift width of the imaging range, each of the plurality of selected registration information.
