Abstract: The provinces and cities located in the Yangtze River Economic Belt are confronted with unbalanced and uncoordinated developments in the fields of ecology, innovation, and the economy sectors. An examination of the coordination relationships within these three areas may have significant importance for both theoretical and practical purposes. Using multiple empirical analysis methods, including the Super-Efficiency SBM-DEA model, the Entropy Weight Linear Weighting method, and the Entropy Weight TOPSIS method, this study respectively evaluated the haze governance efficiency, the green technology innovation index, and the low-carbon high-quality development index of the provinces and cities along the Yangtze River Economic Belt from 2009 to 2020. The coordination between these three aspects was also explored, based on the coupling coordination degree model. The results indicated that: (1) The haze governance efficiency significantly differed from the green technology innovation index and the low-carbon high-quality development index at both the provincial and regional levels. (2) The coupling coordination of the ternary system displayed an overall increasing trend, with a positive spatial spillover effect and a spatial differentiation identified as "higher in the eastern region and lower in the central region". (3) The gap in coordination among the provinces and cities exhibited heterogeneity, but the divergences between regions were reducing over time. Based on these findings, this article put forward several proposals for enhancing the coordinated growth of the Yangtze River Economic Belt. These proposals included the optimization of resource and factor allocation, the design of tailored and targeted improvement strategies, and the implementation of cross-regional collaboration mechanisms.