Sustainable cities are the focus of attention in many areas. The advent of the intelligent era and the evolution of the network society have promoted the study of the relationship between technology and sustainable development. Sustainable cities need innovative research methods and contents. The domestic academic circles have not paid enough attention to the forefront of sustainable cities. The national territory spatial plan also needs to draw on and integrate the relevant theories of sustainable cities. With the help of CiteSpace software, this article systematically reviews the current research situations and development trend of sustainable cities. The paper analyzes its evolution and research hotspots, and finds that the research on sustainable cities has mainly experienced four stages: germination, rise, growth and diffusion. International sustainable cities research mainly focuses on three aspects: climate change, urban governance and smart cities. The research changes from "sustainable" to "smart sustainable". Big data-assisted urban planning has become a trend, and the co-governance of diverse community stakeholders has gradually increased. However, the research and practice of smart sustainable cities in China are insufficient, the evaluation index system of sustainable cities is not perfect, the international experience is lacking, and the research on joint urban-rural governance is insufficient. The combination of the new sustainable cities research framework and the territorial development plan will be the key to future research. The practice of sustainable cities in China is not just for cities, but for urban-rural co-governance, which is also a concentrated manifestation of sustainability in terms of time, space and society. In the evaluation index system of sustainable cities, rural development indicators should be considered. And the issues of rural intelligence, environmental compatibility and technology compatibility in the national territory spatial plan are also important aspects of sustainable cities. Sustainable cities should focus on the coordinated development of nature, society and technology, not only to protect the environment and natural resources, but also to reform the urban and rural governance model and system. The national territory spatial plan is an important foundation for China to achieve sustainable cities. Starting from the proposition of "urban-rural China", urban-rural co-governance is the focus of China's sustainable urban development and research, and is also the main content of the national territorial development planning. Only through the reform of the combination of multi-dimensional systems can the concept of sustainable cities be implemented, and the integration of urban and rural areas can be achieved with the help of intelligent technology. In the future, China's sustainable cities research and practice will become a focus.