This book constitutes refereed proceedings of the 14th International Conference on Parallel Computational Technologies, PCT 2020, held in May 2020. Due to the COVID-19 pandemic the conference was held online.The 22 revised full papers and 2 short papers presented were carefully reviewed and selected from 124 submissions. The papers are organized in topical sections on high performance architectures, tools and technologies; parallel numerical algorithms; supercomputer simulation.