This book constitutes the proceedings of the 6th International Conference on Internet of Things, ICIOT 2021, held virtually as part of SCF 2021, during December 10-14, 2021. The 8 full papers presented in this volume were carefully reviewed and selected from numerous submissions. The conference Internet of Things (ICIOT 2021) covers state-of-the-art technologies and best practices of Internet of Things, as well as emerging standards and research topics which would define the future of Internet of Things.