Abstract: Based on Normalized Difference Vegetation Index (NDVI) remote sensing data from 2001 to 2023, the characteristics of vegetation coverage change in Ya’an City were analyzed with the maximum synthesis method and Sen+MK trend analysis method. The results showed that: (1) The annual average NDVI in Ya'an City reached 0.85, showing a slow rising trend in general. Vegetation coverage was highest in summer, followed by autumn, spring, and lowest in winter. (2) Spatially, vegetation coverage in the northern region was generally better than that in the southern region. Most of the areas with the highest vegetation coverage are nature reserves and forest parks, while most of the areas with the lowest vegetation coverage are alpine areas and urbanization areas of counties. (3) The area of vegetation coverage in Ya 'an showed an increasing trend and maintained a relatively stable state accounted for more than 95%, the areas with increased vegetation were mostly distributed in the low mountain belt and the two sides of the river valley, while the areas with decreased vegetation were mostly urbanization areas. In summer and autumn, vegetation coverage in most areas remained relatively stable, accounting for 70.83% and 61.39%. In winter and spring, vegetation coverage in most areas showed an increasing trend, accounting for 72.16% and 60.29%, respectively.