China's urbanization has made world-renowned achievements, but the task of improving the quality of urbanization is still arduous: the problem of urbanization of the agricultural transfer population is still prominent; the spillover effect of central cities is still weak; and the urban economic efficiency is still low.As the main carrying force of China's economy, urban agglomerations better promote spatial allocation of resources. As a country with a large population, it is particularly important to build a large city group system to promote the development of urbanization in China. With the application of Internet +, AI and big data, the age of city intelligence has arrived. Data sharing and collaborative governance between cities and urban agglomerations have become a reality, and it is possible to build a large-scale urban agglomeration system.In the new stage of urbanization, the characteristics of big country and the era of wisdom determine that China's urban system will be multi-layered, and the big country urban agglomeration system should become the main body of China's urban system in the future. It is not only the requirement of China's urbanization development, but also the requirement of China's high-quality economic development to promote the high-quality development of urbanization under the guidance of building a large-scale urban agglomeration system. It is necessary to consolidate the foundation of big country urban agglomeration system from the micro level by accelerating the citizenization of agricultural transfer population; improve the system literacy of big country urban agglomeration from the medium level by giving play to the spillover and driving effect of central cities; and develop the pattern of big country urban agglomeration from the macro level by improving the economic efficiency of cities.
