This book constitutes the refereed proceedings of the 11th International Conference on Cryptology in India INDOCRYPT 2010 held in Hyderabad India in December 2010. The 22 revised full papers were carefully reviewed and selected from 72 submissions. The papers are organized in topical sections on security of RSA and multivariate schemes; security analysis pseudorandom permutations and applications; hash functions; attacks on block ciphers and stream ciphers; fast cryptographic computation; cryptanalysis of AES; and efficient implementation.