This book constitutes the refereed proceedings of the 10th International Conference on Applied Cryptography and Network Security, ACNS 2012, held in Singapore, in June 2012.The 33 revised full papers included in this volume were carefully reviewed and selected from 192 submissions. They are organized in topical sessions on authentication, key management, block ciphers, identity-based cryptography, cryptographic primitives, cryptanalysis, side channel attacks, network security, Web security, security and privacy in social networks, security and privacy in RFID systems, security and privacy in cloud systems, and security and privacy in smart grids.