Since population is the key factor of urban development, the change of population scale and its structural characteristics are related to the rise and fall of a city. In this paper, shrinking cities have been identified based on the data of the last three censuses, which reveals their demographic characteristics. Meanwhile, the new trends, patterns and characteristics of the spatio-temporal evolution of urban contraction during the seventh general population period in China by using Dagum Gini coefficient and standard deviation ellipse. The results show that: 1) The rapid development of urbanization and urban shrinkage coexist, and the shrinking cities show a more obvious trend of aging and shortage of working-age population. The population problems of the shrinking cities are intertwined with the urbanization problems of other cities, which restrict their further development. 2) The number and intensity of population shrinking cities in China increased, and the shrinking regions showed a trend of diffusion. The trend of urban shrinking center of gravity was different from that of population distribution center of gravity shift. 3) The urban contraction has the characteristics of agglomeration in space as well as outward diffusion, and the differences of regional population distribution reveal the internal motivation of urban sprawl diffusion with shrinking population to a certain extent. This paper argues that: 1) The deflating the city could apply “open source” and “throttling” dual tactics, which should transfer economic development manner from element accumulated growth to efficiency improvement. As the main way of promoting the quality of economic growth, meanwhile, it should improve social security and pension service system at the same time that curb brain drain, and alleviate the problems of excessive social burden caused by the aging population through a bottom-line guarantee policy. 2) In the face of the diffusion trend of shrinking cities and the distribution trend of more and more concentrated population, we can restrain the spread of urban contraction and excessive concentration population, by making metropolitan areas bigger and stronger. 3) Balanced regional development is a long-term work to alleviate the trend of urban contraction and spread.
