This book constitutes the refereed proceedings of the 11th International Conference on Applied Cryptography and Network Security, ACNS 2013, held in Banff, Canada, in June 2013. The 33 revised full papers included in this volume were carefully reviewed and selected from 192 submissions. They are organized in topical sections on Cloud Cryptography; Secure Computation; Hash Function and Block Cipher; Signature; System Attack; Secure Implementation - Hardware; Secure Implementation - Software; Group-oriented Systems; Key Exchange and Leakage Resilience; Cryptographic Proof; Cryptosystems.