This book constitutes the revised selected papers of the 13th International Conference on HPCST 2023, held in Barnaul, Russia, during May 19–20, 2023. The 21 full papers included in this book were carefully reviewed and selected from 81 submissions. The papers are organized in topical sections as follows: Hardware for High-Performance Computing and Signal Processing; Information Technologies and Computer Simulation of Physical Phenomena; Computing Technologies in Data Analysis and Decision Making; Information and Computing Technologies in Automation and Control Science; Computing Technologies in Information Security Applications.