The 2021 3rd International Conference on Wireless Communications and Smart Grid（ICWCSG2021) will be held on August 13-15, 2021 in Nanjing, China. ICWCSG 2021 is to bring together innovative academics and industrial experts in the field of wireless communications and smart grid to a common forum. The primary goal of the conference is to promote research and developmental activities in wireless communications and smart grid and another goal is to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working all around the world.