A biometric information processing apparatus includes: a biometric information acquiring unit which acquires a user's biometric information and generates a biometric input image representing the biometric information; and a processing unit. The processing unit implements: generating a first intermediate image by applying first image processing to the biometric input image; generating a second intermediate image by applying second image processing to the biometric input image; detecting, from each of the first and second intermediate images, a singular point candidate; calculating a distance between the singular point candidates detected from each of the first and second intermediate images for the same singular point contained in the biometric information; calculating a quality metric for the biometric input image based on the distance; and if the quality metric is not higher than a predefined threshold value, then prompting the user to have the user's biometric information reacquired by the biometric information acquiring unit.