This book constitutes the refereed proceedings of the 15th International Conference on Cryptology in Africa, AFRICACRYPT 2024, held in Douala, Cameroon, in July 2024. The 19 full papers included in this book were carefully reviewed and selected from 35 submissions. They are organized in topical sections as follows: symmetric key cryptography; advanced primitives; post-quantum cryptography; elliptic curve cryptography and RSA; lattice-based cryptography constructions; and lattice-based cryptography cryptanalysis.