The evaluation of environmental status and the analysis of the influencing factors are significant to the transformation and high-quality development of mature coal cities. Choosing five typical mature coal cities in China as the case study, this study constructed the comprehensive evaluation system of ECC (environmental carrying capacity). It assessed the temporal variation of ECC from 2010 to 2019 with normal cloud mode. Then the main influencing factors were identified by analyzing the interaction mechanism between factors via BP-DEMATEL mode. The results indicated that: (1) The ECC level of most cities improved significantly. (2) The ECC levels of resource-environment subsystem were higher than that of society-economy subsystem. (3) Proportion of environmental protection spending, comprehensive utilization rate of industrial solid and atmospheric pollutants emission intensity were the main driving influencing factors, while the proportion of subsidence area and urbanization rate were the main characteristic influencing factors of most cities. Meanwhile, each city has some main influencing factors which are different from each other. This study compares the changing trend of ECC in different mature coal cities and analyzes the reasons, which provides scientific basis and decisionmaking reference for the formulation of relevant policies.