Due to its unique geographical location and development potential, the Yangtze River Economic Belt (YEB) has emerged as one of the most economically developed regions in China. The study employs remote sensing data to conduct a coupled coordination analysis of the ecological environment and urbanization processes of the three major urban agglomerations in the YEB using the Coupled Coordination Model (CCD). The results show that (1) the mean RSEI values of the three urban agglomerations initially declined, then fluctuated upwards; (2) the CNLI values of all three urban agglomerations maintained a continuous increase, with the urbanization level of the Yangtze River Delta urban agglomeration being significantly higher than that of the other two urban agglomerations; and (3) The degree of coupling and coordination of the Yangtze River Delta urban agglomeration was significantly higher than that of the Chengdu-Chongqing urban agglomeration and the middle reaches of the Yangtze River urban agglomeration.