Abstract: Taking 16 cities in the Yangtze River Delta as an example, the urbanization and environmental index evaluation system, and the coupling coordination model between urbanization and ecological environment, were constructed, and the spatial and temporal differences were comparatively analyzed.The results showed that from 2012 to 2016, the comprehensive score of urbanization in the Yangtze River Delta was increased with fluctuation generally, and the comprehensive scores of urbanization among cities were with obvious differences;the temporal differences of urbanization showed decreased from the central to both side, and the urbanization comprehensive score was significantly different between Taizhou, Yangzhou, Shaoxing, etc., and Shanghai, Nanjing, Hangzhou, etc.From 2012 to 2016, the comprehensive scores of ecological environment of the cities in the Yangtze River Delta also showed a general upward trend with fluctuation;the ecological environment level was relatively even overall except for Nanjing, Taizhou, etc.There was obvious correlation between the comprehensive scores of ecological environment and urbanization, and the coupling coordination degree of urbanization and ecological environment among cities in Yangtze River Delta were with significant difference.On the whole, the coordination degree of urbanization and ecological environment for the Yangtze River Delta urban agglomeration was increasing, and most of the cities were with the basic coordination lever, but great differences were existed among different cities.