A biometric authentication device includes, an acquisition unit configured to repeatedly image a biological part of an authenticated person while changing a relative position with respect to the biological part so as to acquire time-series biological images; a detection unit configured to detect a pixel corresponding among the biological images from the time-series biological images; an extraction unit configured to extract a pixel of which a pixel value includes a surface reflection component from the biological part, from each of the time-series biological images, on the basis of a degree of divergence of temporal variation of a pixel value of the detected pixel in the time-series biological images from an estimation result of temporal variation; a generation unit configured to correct the pixel value of the extracted pixel on the basis of a pixel value; and an authentication unit configured to perform personal authentication of the authenticated person.