The rapid development of intelligent technology not only provides new technical means for the monitoring and regulation of urban man-land system, but also has a systematic impact on the element structure, coupling relationship and dynamic evolution of urban man-land system. It is imperative to explore the theory of building a man-land system for smart cities. Based on the interpretation of the connotation of the smart city man-land system, this paper discusses the theoretical basis of the smart city man-land system from the aspects of flow space, technology-man-land coupling and resilience system, and then puts forward the conceptual model of the smart city man-land system. On the one hand, we should explore the spatial scale changes of the interactions among human activities, elemental flows, and geographic environments, and further investigate into the cross-scale collaboration, tele-coupling, and feedback between activity systems and geographic environment systems regulated by intelligent technologies. On the other hand, we should pay attention to temporal elasticity, flexibility and fragmentation of the interactive coupling between residents' activities and urban geographical environment caused by the wide application of intelligent technology. Then it is necessary to carry out the monitoring, management and dynamic optimization with the smart city man-land system. Facing the future, the research on man-land system of smart cities needs to focus on the spatio-temporal coupling process of elements, elemental composition and impact mechanism, modeling methods and evaluation, comprehensive regulation and optimization path, etc. Finally, from the aspects of human behavior patterns and activity changes brought about by smart technology, spatial intelligence, virtual reality correlation, etc., the research prospect of theoretical exploration, analysis method innovation and sustainable regulation of smart city man-land system is proposed. All in all, based on the coupling of people, technology and urban space, we build the theoretical framework of smart city man-land system adapted to China's national conditions in consideration of the trend of high penetration and integration of China's new infrastructure and smart city services in production, living and governmental management. This framework could support the innovation of urban geography theory and method and the practical needs of "smart brain", digital twin city construction.