Abstract: Ecological transformation is a crucial direction for comprehensive land consolidation across the entire region in the new era. Identifying the spatio-temporal differentiation characteristics of ecological quality in agricultural land consolidation serves as the foundation for planning and decision-making. Based on the Remote Sensing-based Ecological Index (RSEI) model, this study delves into the spatio-temporal differentiation patterns and dynamic processes of ecological quality in the project areas, focusing on 267 agricultural land consolidation projects in Qijiang District from 2000 to 2020. This study further compares and analyzes the ecological quality characteristics of the project areas across different consolidation frequencies, thereby revealing the underlying causes of ecological quality differences observed in agricultural land consolidation areas. The results show that: ① In the past 20 years, the ecological environment quality in the agricultural land consolidation areas of Qijiang District has been generally good, with the RSEI exhibiting a "V"-shaped trend of initial decline followed by an overall increase. From a long-term perspective, agricultural land consolidation has significantly contributed to a positive improvement in regional ecological quality. By analyzing different consolidation periods, it becomes evident that the implementation of Phase 1 projects (2000-2010) caused some disturbance to the regional ecological environment, whereas the implementation of Phase 2 (2011-2015) and Phase 3 (2016-2020) projects facilitated the optimization of ecological quality in the project areas. Considering the years of agricultural land consolidation project implementation, the ecological quality has shown a continuously improving trend after 5, 10, and 15 years, indicating that agricultural land consolidation projects have a sustained and profound impact on the restoration and optimization of regional ecological environments. ② From 2000 to 2020, the ecological quality within the 267 agricultural land consolidation project areas was predominantly good, with the area of good-quality patches accounting for over 55% of the total project area, while the proportion of inferior and poor-quality patches was less than 3%. When analyzed from different consolidation phases, the main feature of ecological degradation during the implementation of Phase 1 projects was the transformation of a significant number of good and excellent ecological quality patches into moderate and good ones. In contrast, Phases 2 and 3 projects primarily contributed to the improvement of the regional ecological environment through the continuous transfer and optimization of a substantial amount of moderate and good-quality patches. ③ There is a positive correlation between the number of agricultural land consolidation efforts and the ecological environment within the project area. In other words, the more frequent the consolidation of agricultural land in the same region, the more significant the improvement in the ecological environment becomes. ④ The changes in RSEI within agricultural land consolidation areas are the result of a combination of natural and socio-economic factors. For Phase 1 projects, the primary influencing factors were the interaction between construction scale and newly added cultivated land. In contrast, for Phase 2 projects, the strongest explanatory power was attributed to the interaction between project type and elevation. The research results enhance the understanding of the ecological quality changes associated with agricultural land consolidation and provide valuable insights and references for the implementation of agricultural land consolidation projects and ecological monitoring in hilly and mountainous regions.