With the rapid development of the global economy, the contradiction between economic development and environmental degradation becomes increasingly severe. People have started to realize the importance of environmental protection during the course of economic development. The urban agglomeration on the middle reach of the Yangtze River occupies an important place in China's regional development, and it belongs to a key zone in territorial development. Development of the urban agglomeration must adhere to the concept and principles of ecological civilization. This article evaluates the state of ecological civilization in the urban agglomeration on the middle reaches of the Yangtze River between 2009 and 2013, using a combined entropy weight and TOPSIS method. This article analyzes the cause and key factors that make ecological civilization vary by using an Environmental Kuznets Curve and obstacle degree model. Using global spatial auto-correlation analysis, this article measures the degree of spatial agglomeration for the urban agglomeration on the middle reaches of the Yangtze River. In addition, this article conducts a visual cluster analysis of ecological civilization for different regions using the Jenks natural breaks classification method. The four main research findings are as follows:(1) The five key factors affecting the ecological civilization of the urban agglomeration on the middle reaches of the Yangtze River are:GDP per capita, per capita retail sales for social consumer goods, the service industry's added value as a portion of GDP, total available water resources per person, and per capita annual disposable income for urban residents. (2) In the greater Wuhan megalopolis, Wuhan's ecological civilization is maintained better than its surrounding cities; this ecological civilization gap between Wuhan and its surrounding cities is evident. The Changsha-Zhuzhou-Xiangtan urban agglomeration follows the Changsha-Zhuzhou dual-core model, partially driving the ecological civilization development of nearby cities, while exerting little effect on the ecological civilization of relatively remote cities. The ecological civilization of the cities and areas surrounding Poyang Lake differs slightly. Over the past five years, the ecological civilization of these cities and areas has been developing noticeably. (3) The clustering characteristics of the urban agglomeration on the middle reaches of the Yangtze River have changed from a weak negative correlation to a weak positive correlation between 2009 and 2013; in 2012, it started showing a strong tendency towards agglomeration. (4) The ecological civilization of Xiangyang and Yichang degrades year by year. It has fallen from the upper part of the ecological civilization Kuznets Curve to the lower part. Economic stimulus contributes little to ecological civilization. The sustainability of ecological civilization construction of Jiujiang is insufficient and has great volatility. It is unable to maintain a good level of ecological civilization over a long period.