In order to improve the green construction level of highways in dense urban areas，the project characteristics and engineering requirements of the Nansha-Zhongshan Expressway were analyzed，and the concept of green development was implemented in the whole life cycle of highway design，construction，operation，maintenance，and management.The research and development of ten innovative technologies in four categories were highlighted，including industrial intelligent construction of highway bridges，comprehensive utilization of highway resources，environmental protection of highways in coastal wet areas，and integrated design of transportation and tourism in the Guangdong-Hong Kong-Marco Greater Bay Area.Among them，the prefabricated beam annular production line and non-standard eight-lane were the unprecedented technologies first used in the project.In addition，the technical system of green highway bridges in typical urban agglomerations was initially constructed，and the key development directions in the future were prospected to enrich and improve the technical system for green highway construction in the Guangdong-Hong Kong-Marco Greater Bay Area.This provided a reference for the sustainable development of other highly urbanized regions.