The present disclosure discloses a fingerprint identification device, a fingerprint identification method and a touch screen. The fingerprint identification device comprises: an optical sensor with a receiving surface configured to receive fingerprint reflected light; and a lens assembly configured to converge the fingerprint reflected light toward the receiving surface of the optical sensor, wherein the lens assembly includes a liquid crystal lens configured to converge the fingerprint reflected light toward the receiving surface of the optical sensor by rotating liquid crystal molecules at different angles upon energization.