A biometric authentication device determining whether or not a user is to be authenticated, by matching biological information of a finger of the user and biological information of a palm thereof against biological information of a finger of a registered user and biological information of a palm thereof, the biometric authentication device includes, a first sensor configured to generate a first biological image in which the biological information of the finger of the user is captured; a second sensor configured to generate a second biological image in which the biological information of the palm of the user is captured; a guiding member configured to regulate a position of the finger of the user; an object area detection unit configured to detect a first object area in which the biological information of the finger is captured on the first biological image; and a position determination unit configured to determine.