1. A fake finger discrimination device, comprising: a fingerprint sensor sensing a rotating finger to obtain fingerprints with different rotating angles of the rotating finger in a fake finger discrimination mode through a single rotation of the rotating finger clockwise and/or anticlockwise without the rotating finger separating from the fingerprint sensor; and a control processor electrically connected to the fingerprint sensor to judge whether one of the fingerprints of the single rotation matches another fingerprint by way of rotation correlation comparison, wherein the rotation correlation comparison is to compare the fingerprints with different rotating angles of the rotating finger; wherein if one of the fingerprints matches another fingerprint by way of the rotation correlation comparison, the finger is determined to be true, otherwise the finger is determined to be fake.