Urban growth and shrinkage are the inevitable results of rapid urbanization.Excessive growth or shrinkage will bring problems such as resource mismatch and ecological environment deterioration.Based on the nighttime light data of China's districts and counties from 1992 to 2019,this paper explores the temporal and spatial dynamic characteristics and underlying causes of urban growth and shrinkage in China,with purpose to provide reference for policy-making on future urbanization,balanced allocation of resources and national development.The results show that urban growth and shrinkage alternate in China with increasingly obvious polarization between growth and shrinkage.Centered in Henan's Nanyang city,the urban growth is mainly a belt structure supplemented by points,in which the belts include the coastal urban belt and the recently formed "Beijing-Zhengzhou-Nanchang" urban belt,and the points refer to inland provincial capitals as agglomeration growth cores.While the urban shrinkage,centered in Shaanxi's Ankang city (shifted from Hebei's Xingtai city),has gradually changed from scattered point shrinkage to belted shrinkage along "Beijing-Xi'an-Chengdu-Kunming".The underlying reasons of urban growth and shrinkage in China include global financial cycle,industrial structure transformation,national policies,etc.