ICGHIT (International Conference on Green and Human Information Technology) is an international conference focusing on green and information technologies oriented to humanity. The goal of ICGHIT is to form a platform to seek the advancement of green technology and human related IT in an interdisciplinary manner. The main topics of the conference are green information technology, communication and IoT, computer and network security, multimedia and signal processing, control and intelligent system, and SW/HW design, architecture & development. Many research papers on advanced technology will be presented and the various products of multiple companies will be exhibited. We hope to provide good chances about the topics for technical exchange and advancement, mutual cooperation among the participants, and local development of the country in which the conference holds. We believe that green technology and human IT are able to produce a synergy to enhance human welfare and humanity in present and future technological society. A philosophy of the conference is the achievement of the dream of IT that is to improve human welfare and happiness. Therefore, we emphasize humanity as well as technology. We hope that you have chances to meet researchers interested in the areas and to be a friend with them. We will make the conference more open and friendly. Welcome to ICGHIT 2021!