This book constitutes the refereed proceedings of the 12th International Conference on Security, Privacy, and Applied Cryptography Engineering, SPACE 2022 held in Jaipur, India, during December 9–12, 2022.The 18 full papers included in this book were carefully reviewed and selected from 61 submissions. They were organized in topical sections as follows: symmetric cryptography; public-key cryptography, post-quantum cryptography, zero knowledge proofs; hardware security and AI; and network security, authentication, and privacy.