[Objective] The vegetation cover change characteristics and their water-sediment effects in Qinjiang River basin were investigated in order to provide scientific support for river basin management and river watersediment regulation. [Methods] Based on the monthly and annual data of water and sediment, NDVI, and precipitation from 2000 to 2021, as well as the annual NDVI, precipitation, and temperature data during the vegetation growing season from 2000 to 2024, this study used correlation analysis, partial correlation analysis, and multiple linear regression model analysis to analyze the interannual and seasonal changes of vegetation cover and their water-sediment effects. In addition, multiple regression residual analysis was used to explore the driving factors of vegetation cover change. [Results] ① From 2000 to 2021, vegetation cover in the Qinjiang River basin showed continuous improvement, with NDVI exhibiting an increasing trend and a significant negative correlation with sediment load. The multiple linear regression results indicated that vegetation cover and precipitation effectively explained sediment load changes: an increase of 1 mm in annual precipitation combined with an increase of 0.1 in the annual mean NDVI was associated with a reduction of 3.05×10⁴ t in annual sediment load.② Seasonal changes in NDVI in the Qinjiang River basin followed the order of summer > autumn > spring > winter. The regulation of water-sediment processes by vegetation exhibited pronounced seasonal differences. Vegetation showed the strongest sediment retention effect in summer, with a negative correlation between NDVI and sediment load, whereas positive correlations were observed in spring and winter, indicating the distinct seasonal asymmetry of soil and water conservation effects.③ Climate change and human activities jointly accounted for more than 90% of the total contribution to vegetation cover change. Temperature increase and afforestation were the main drivers of vegetation restoration. The middle and lower reaches, characterized by abundant precipitation and high temperature, showed greater contribution than the upper reaches. In contrast, urban expansion exerted an inhibitory effect on vegetation cover. [Conclusion] Vegetation restoration in Qinjiang River basin exhibits a significant sediment reduction effect. The multiple linear regression model can effectively simulate sediment load changes, demonstrating potential applicability in other river basins within the Beibu Gulf region. Future attention should be paid to ecological construction in urban areas. The findings can provide scientific support for watersediment regulation, ecological restoration, and river basin management under the background of the Pinglu Canal construction.