1. A biometric authentication apparatus, which detects biometrics characteristic data of a living body and performs individual authentication, comprising: a detection device which detects the living body and obtains biometrics information; a control unit which extracts, from said biometrics information, comparatively coarse first biometrics characteristic data and comparatively fine second characteristic data on a user; and a biometrics information database file, in which is stored, as biometrics information on said user, said first biometrics characteristic data and said second biometrics characteristic data, wherein said control unit extracts comparatively coarse first biometrics characteristic data and comparatively fine second characteristic data for use in verification from said biometrics information obtained by said detection device, calculates the degree of similarity between said first biometrics characteristic data for verification and first biometrics characteristic data sets stored in said biometrics database file, determines the order of verification with second biometrics characteristic data sets stored in said biometrics database file according to said degrees of similarity, and performs verification of said second biometrics characteristic data for verification against said stored second biometrics characteristic data sets according to said verification order.