1. A signature collation apparatus which performs, on the basis of the degree of coincidence between an input image of a signature and a reference image of a signature to be compared with said input image, signature collation between the input image and the reference image, comprising: a corresponding point searching unit which searches corresponding points between the input image and the reference image; and a calculation unit which, on the basis of a transformation-corrected image obtained by correcting transformation of the signature of the input image on the basis of the corresponding points searched by said corresponding point searching unit, a coincidence coefficient of the reference image and a non-transformation coefficient between the input image and the reference image, calculates a collation value between the transformation-corrected image and the reference image.