This book constitutes the proceedings of the Third International Conference on Cryptology in Africa, AFRICACRYPT 2010, held in Stellenbosch, South Africa, on May 3-6, 2010. The 25 papers presented together with three invited talks were carefully reviewed and selected from 82 submissions. The topics covered are signatures, attacks, protocols, networks, elliptic curves, side-channel attacks and fault attacks, public-key encryption, keys and PUFs, and ciphers and hash functions.