This three-volume set constitutes the proceedings of the 24th International Conference on Applied Cryptography and Network Security, ACNS 2026, held in Stony Brook, USA, during June 2026.

The 59 full papers included in these proceedings were carefully reviewed and selected from 282 submissions. This volume, LNCS 16571, contains 20 papers organized into three topical sections: Post-Quantum Cryptography, Cryptographic Primitives and Proof Systems, and Secure Protocols and Multi-Party Computation.