In this paper, a chaotic encryption framework based on fractional wavelet packet transform (FrWPT) is proposed for securing palmprint data. The palmprint image is first transformed into FrWPT domain with chaotically generated transform orders followed by the alteration of FrWPT coefficients using Hessenberg decomposition. Finally, a reliable decryption scheme is presented to reconstruct original plamprint image from the encrypted data only with the valid keys. Simulated results and analysis validate the efficiency and robustness of the proposed technique. © 2012 Published by Elsevier Ltd.