A biometric authentication device collates pre-registered biometric data for authentication with biometric data acquired during authentication. An imaging section images biometric data acquired by penetration through the finger by near-infrared light from a near-infrared light irradiating section. A control section acquires the biometric data acquired by the imaging section. A visible light irradiating section irradiates a finger inserting section where the finger is inserted with visible light. The visible light irradiating section starts irradiation of the visible light before the imaging section acquires the biometric data. The control section sets irradiation luminosity from the visible light irradiating section to be lower in a case where luminosity of an imaging screen of the biometric data acquired by the imaging section is higher than luminosity appropriate for authentication, and collates the biometric data in the case where the irradiation luminosity is set to be lower with the pre-registered biometric data for authentication.
