Based on MODIS NDVI data from 2000 to 2024, this study employs linear trend analysis, Mann–Kendall significance testing (MK), and Hurst index analysis to investigate the spatiotemporal characteristics of vegetation cover changes and future trends in the Shiyang River Basin over the past 25 years. Results indicate: (1) Overall NDVI in the Shiyang River Basin showed a significant upward trend from 2000 to 2024, reflecting an overall improvement in vegetation cover; (2) Spatially, vegetation improvement was concentrated in the oases and mountainous areas of the middle and upper reaches, while degradation occurred in the arid desert areas downstream and some peripheries of irrigated zones; (3) The Mann–Kendall -test indicates improvement trends in most areas of the basin; (4) Hurst index results demonstrate strong persistence in the basin’s NDVI time series, suggesting continued vegetation improvement overall, though downstream regions face certain degradation risks. These findings reveal the phased achievements and spatial variations in ecological restoration within the Shiyang River Basin, providing scientific basis for regional ecological construction and water resource management.