A device is not able to detect the forgery of a finger with high accuracy bey the comparison of a reflected light image and a transmitted light image that are obtained from the same finger. A determination device is provided with an input means for receiving the reflected light image obtained by photographing a fingerprint of a finger with light reflected from the surface of the finger and the transmitted light image obtained by photographing the fingerprint of the finger with light transmitted through the finger, and a determination means for comparing the reflected light image and the transmitted light image, and outputting a real-forgery determination result of the fingerprint of the finger.
