The four-volume proceedings set LNCS 14601-14604 constitutes the refereed proceedings of the 27th IACR International Conference on Practice and Theory of Public Key Cryptography, PKC 2024, held in Sydney, NSW, Australia, April 15-17, 2024. The 54 papers included in these proceedings were carefully reviewed and selected from 176 submissions. They focus on all aspects of signatures; attacks; commitments; multiparty computation; zero knowledge proofs; theoretical foundations; isogenies and applications; lattices and applications; Diffie Hellman and applications; encryption; homomorphic encryption; and implementation. .