Abstract: To reveal dynamic characteristics of regional water environment carrying capacity, this study designed an indicator system consisting of three subsystems (socioeconomic subsystem, water resource subsystem and water eco-environment subsystem), and determined the weights of indicators. Fuzzy comprehensive assessment model was used to map out the dynamic trend of water environment carrying capacity. Obstacle degree model was used to analyze the obstacle factors. The results showed that:(1) The water environment carrying capacity steadily increased from 0.3450 in 2006 to 0.4700 in 2016. (2) There were great differences among the subsystems. The evaluation index of the water eco-environment subsystems reached more than 0.6151 with some fluctuations, and the economic subsystem increased from 0.4276 to 0.6356, which laid a solid foundation for the improvement of water environment carrying capacity. The water resource subsystem, with evaluation index lower than 0.2000, was found to be the top factor impacting water environment carrying capacity. (3) According to the analysis of obstacle degree, the factors with higher obstacle degrees were the population density, water resource utilization rate, per capita water resources, and water quality compliance rate. The water resource subsystem was the dominant factor that influenced the water environment carrying capacity. The primary challenges to improve the water environment carrying capacity are dense population and low compliance rate of water quality. Attention should be paid to these factors when improving the water environment carrying capacity in Nanjing City.