In order to monitor the spatiotemporal variations of ecological environment quality in the Aksu region comprehensively and timely, this study utilized the Google Earth Engine (GEE) platform to construct a remote sensing ecological index (RSEI) based on MODIS multispectral sensor data from 2005, 2010, 2015, and 2020. Additionally, the Moran index and Geo-detector were employed to investigate the spatial and temporal evolution of ecological quality and identify impact factors in the Aksu region. The findings indicated that: (1) The RSEI in the Aksu area increased from 0.24 to 0.27 between 2005 and 2020, exhibiting a fluctuating upward trend in ecological environmental quality. The high RSEI values were predominantly observed in the northern edge and central oasis region, while the low values were concentrated in the desert and Gobi region. (2) Throughout 2005-2020, the overall Moran index of the RSEI ranged between 0.80 and 0.87, signifying a strong positive correlation in the Aksu region, with high-high (H-H) and low-low (L-L) clusters being dominant. (3) From 2005 to 2020, the explanatory power of various factors in spatial heterogeneity (q-value) varied to different extents, with land use and rainfall identified as key drivers. Furthermore, the influence of interaction detection surpassed that of individual factors. This research provides valuable data and methodological references for the protection of the local ecological environment.