A biometric authentication apparatus is provided. The biometric authentication apparatus includes one or more converters that convert a transmit signal of an electrical signal into a vibration signal of a mechanical signal and transmit the vibration signal vibrating within a set frequency range to a user, one or more sensor that receive a biometric signal corresponding to the vibration signal from the user and convert the biometric signal into a receive signal of an electrical signal, an authentication module that extracts anatomical feature information of the user from the receive signal and determines whether the user is a registered user based on the anatomical feature information, and a memory that stores a database for the registered user. The biometric signal is a frequency-based signal modified to include the anatomical feature information while the vibration signal passes through at least a portion of the body of the user.