Abstract: Since the late Qing Dynasty, China’s city system has experienced four stages: the narrow autonomous city system, the zigzag growth of the narrow administrative city system, the rapid increase of the number of the wide administrative city system, and the improvement of the quality of the regional governance city system. As the three elements of the government district, the city town system, the government district space and the administrative unit correspond to the realization of the coordination of the system and the element urbanization, the finding of the scale unit of the city system, and the optimization of the city organization system. In order to give full play to the system efficiency of the city system in the modernization of urban governance, it is necessary to carry out continuous reform on the three elements of government and district. Recently, novel coronavirus pneumonia has raised alarm for the reform of municipal system. In the future, the development of city system should pay attention to the reform measures such as enriching the type of construction system, optimizing the spatial form and reducing the administrative level to improve the city toughness.