A biometric information processing apparatus, a method for processing biometric information, and a biometric information processing program are provided for analyzing biometric information that is obtained by combining and reconstructing two or more captured partial biometric images, and a mismatching region is extracted from the combined biometric image. Then, a mismatching region is excluded from the biometric image, and a proper region suitable for identification is extracted. Accordingly, false rejection or the like may be avoided. Moreover, the reliability of biometric identification may be improved, and the number of times of asking a user to reinput his/her biometric information may be reduced. Hence, the convenience is enhanced.