The urban planning industry has always been concerned about conserving and developing historic cities in a sustainable and balanced way. However, unreasonable planning and accumulative effects brought by rapid urbanization prevent the conservation of small-scale famous historic and cultural cities. Taking Tingchow county as an example, this paper focused on sustainable development and the Historic Urban Landscape Approach, and determined the urban functions and specific tasks of various planning of its ancient town with the help of public opinions. This paper mainly aimed at providing guidance on urban decentralization from two perspectives. Firstly, it compared the types of land use and its ratio among famous cities of similar scales, and results showed that it is advisable to reduce three-class residential land use and unnecessary administrative functions. Secondly, it estimated the moderate resident population in different degrees of development, and calculated the upper limit of resource space bearing capacity (REBC) of scenic spots under the guidance of sustainable tourism. Results showed that it is recommended to decentralize and resettle 20%similar to 30% of the resident population, and to control the tourist population below 12,000 per day. As the preliminary work of planning, this paper focused on the scientific planning and availability of decentralization, and reflected an expectation for the mode of public participation and quantitative planning.
