A biometric authentication device including: a biometric information acquiring unit which generates a biometric input image representing user's biometric input information; a storage unit which stores, for each of a plurality of registered users which have been preregistered, a first group feature for each of a plurality of groups set for a registered biometric image representing registered biometric information; and a processing unit. The processing unit: extracts, for each of blocks obtained by dividing the biometric input image, a local feature representing the geometric feature of the biometric input information contained in the block; classifies the plurality of blocks into a plurality of groups by blocks with a similar local feature; extracts a second group feature representing feature of biometric input information for each of the plurality of groups; calculates the degree of difference between each of the plurality of registered biometric information and the biometric input information based on the first group feature and the second group feature; selects a prescribed number of registered biometric information in ascending order of the degree of the difference; and matches the selected registered biometric information with the biometric input information.