This book constitutes the refereed proceedings of the 24th International Conference on Information Technologies and Mathematical Modelling. Queueing Theory and Related Fields, ITMM 2025, held in Krasnoyarsk, Russia, during October 20–25, 2025.The 21 full papers included in this book were carefully reviewed and selected from 83 submissions. They focus on new results in queueing theory and its applications, and also related areas of probabilistic analysis.