As a new first-tier city, Chengdu serves as a crucial ecological demonstration area in the upper reaches of the Yangtze River. Assessing and monitoring the quality of the ecological environment within this region are fundamental tasks for advancing the construction of an ecological civilization. Our analysis revealed that from 2013 to 2022, the average RSEI ranged between 0.4 and 0.6, indicating a gradual improvement in the quality of the ecological environment. Notably, between 2017 and 2022, areas exhibiting excellent ecological quality expanded, while those exhibiting poor quality decreased. Additionally, regions of medium-grade quality remained relatively stable and dominant. Over the past decade, the global Moran’s I values ranged from 0.914 to 0.960, indicating a positive spatial correlation for the ecological quality of Chengdu, albeit with a decreasing degree of clustering. Further analysis of the local spatial autocorrelation of the RSEI revealed ‘high-high’ (H-H) concentrations primarily in the western mountainous areas, attributed to lower urbanization rates and superior ecological conditions. Conversely, ‘low-low’ (L-L) clusters predominantly appeared in central urban zones characterized by intensive social and industrial activities. In addition, the future trend of Chengdu RSEI showed a strong sustainability, reflecting the continuous improvement of the overall ecological environment of Chengdu.