From September 10 to 11, 2020, the 255th Shuangqing Forum of the National Natural Science Foundation of China (NSC) was held in Beijing. Professor Yuan Linwang participated in the forum and made a special report on “Digital Twins and Virtual Experiments for Multi-Scale Modeling of Land and Sea Interfaces”, which reads: Digital Twin and Virtual Experimental Technology establishes digital mapping of the real world and its features, processes and mechanisms by integrating all kinds of observation data and model patterns under a unified space-time framework, and using virtual simulation and other means. The sustainable development of coastal zone involves the interaction of multi-layer, multi-domain and multi-scale elements, the development of digital twin technology and virtual experimental method of multi-scale modeling of land-sea interface, the convergence of multi-domain and multi-scale space-time data under the unified space-time framework, the integrated modeling and big data intelligent analysis of multi-pattern coupling across the circle layer, and the provision of virtual twin coastal multi-modal fusion expression and multi-scenario virtual experiment with real perception and feedback control. The research can effectively connect the whole process of modeling and simulation, diagnosis and attribution, virtual experiment and visual decision analysis for coastal zone sustainability construction, and provide an integrated support platform for land and sea integration and intelligent analysis of integrated data environment modeling environment-expression environment-collaborative environment. The relevant information of this issue of the Shuangqing Forum is as follows: This session is co-sponsored by the Ministry of Geosciences of the Natural Science Foundation, the Department of Management Sciences, the Ministry of Computer Science, the Ministry of Chemical Sciences, the Ministry of Life Sciences, the Ministry of Information Science and the Bureau of Policy, and hosted by Xiamen University. With the theme of “Coastal Belt-Offshore Multi-Interface Cross-Circle Interaction and Sustainable and Healthy Oceans”, the Forum was chaired by Dai Minhan of Xiamen University, Zhou Hongchun, Researcher of the Development Research Center of the State Council, and Zhang 偲 of the South China Sea Ocean Research Institute of the Chinese Academy of Sciences. The Forum was attended by relevant comrades from the relevant ministries of science and policy bureaus, as well as 40 experts and scholars from 25 research institutes in relevant fields in China. A total of 6 thematic reports and 12 thematic reports were scheduled for the current session of the Forum. Combined with their own research work, the participants carefully analyzed and fully discussed the current situation, progress, hot spots and trends of international and domestic research in this field on the three topics of “land-sea interface material energy transportation and its regulation of offshore ecosystems”, “offshore-oceanic material energy exchange and climate and ecological environment effects of its interaction with the atmosphere” and “coupling of marine ecosystem and human socio-economic system”. The experts agreed that it is of great strategic significance to carry out the integration research of cross-circle and multi-interface in coastal zone, to face up to the major needs of the country, and to promote the deep integration of research platforms such as data, observation and mode, to deepen the reform of China’s scientific and technological system, and to promote scientific and technological solutions to social development problems. The meeting defined the spatial region and time scale of the study of the “human-sea composite system” in the coastal zone, put forward a new paradigm of coastal zone research based on the strategy of “diagnosis-attribution-simulation-response”, determined the idea of multi-interface, cross-circle and interdisciplinary chain research in the coastal zone, condensed the core and key scientific issues of the sustainable development of the coastal zone, and looked forward to the “regional earth system integration model coupled by multiple interfaces in the coastal zone”, “the sustainable development path and model of coastal zone land and sea integration”. Digital twin China Sea and the country’s major strategic decision-making support” and other important research directions in the future. Experts at the meeting put forward specific suggestions on how the Natural Science Foundation of China should support the research on sustainable development of coastal zone in the next 5-10 years, and looked forward to launching multidisciplinary and cross-research layout, playing a greater role in top-level design and team organization, so as to urge Chinese scientists to seize this important opportunity, make original results with significant impact, and finally achieve a leading role in the research field of “man-sea composite system” in the coastal zone.