This book focus on innovation, main objectives are to bring the community of researchers in the fields of mechanical design together; to exchange and discuss the most recent investigations, challenging problems and new trends; and to encourage the wider implementation of the advanced design technologies and tools in the world, particularly throughout China. The theme of 2021 ICMD is "Interdisciplinary and Design Innovation" and this conference is expected to provide an excellent forum for cross-fertilization of ideas so that more general, intelligent, robust and computationally economical mechanical design methods are created for multi-disciplinary applications.