A sensor for increasing security using biometric data, a mobile device including the same, and an authentication method of the mobile device are provided. The sensor includes a fingerprint sensor configured to detect fingerprint data of a user contacting a fingerprint acquisition region, a plurality of electrodes, and a bio sensor connected to the electrodes to detect at least one type of biometric data. A first electrode among the electrodes is located such that a finger of the user contacts the first electrode when the finger of the user is in contact with the fingerprint acquisition region.