A secure registration-free fingerprint authentication method based on local structures comprising: extracting descriptor features and local structure features of fingerprint minutiae from an input fingerprint image; conducting quantization and feature selection with respect to the features of the fingerprint minutiae; and encrypting the selected features and then decrypting the encrypted features to obtain the fingerprint image. The method adopts local features for fingerprint authentication, thus avoiding the complex registration in encryption domain. The method lowers the risk of the fingerprint authentication being attacked and improves security.