The two-volume set LNCS 14526 and 14527 constitutes the refereed proceedings of the 19th International Conference on Information Security and Cryptology, Inscrypt 2023, held in Hangzhou, China, during December 9–10, 2023. The 38 full papers and 7 short papers presented in these proceedings were carefully reviewed and selected from 152 submissions. The papers have been organized in the following topical sections: Part I: Signature; blockchain; cryptography primitive; public key cryptography; security and privacy; Part II: System security; cryptography engineering; cryptanalysis; short papers, posters.