Abstract: Proper evaluation of the topographic effects of vegetation change could provide scientific basis for the benefit assessment of ecological stability sustainable development, ecological protection and ecological construction in the Hengduan Mountains Region. Based on MODIS vegetation remote sensing products and DEM data, Sen+M-K trend analysis was used combined with the terrain difference correction method to analyze the relationship between vegetation and terrain factors in the Hengduan Mountains Region from 2000 to 2020. The results show that: (1) Within the 21 years, the distribution pattern of NDVI was higher in the south and lower in the north, higher in low altitudes and lower in high altitudes. NDVI varies significantly with elevation change, and there are obvious differences between ridge and valley. The area of vegetation in stable accounted for 64.13%, and the areas with extremely significant increase and significant increase accounted for 12.54% and 11.77%, respectively. The average annual change rate was 0.013 (10 a)^-1. (2) The distribution and change of NDVI have obvious topographic effects in Hengduan Mountains Region. NDVI fluctuates slightly in the area with elevation less than 3 845 m, and decreases in a stepwise manner above 3 845 m. Although the difference of NDVI is small in different slope directions, the north slope is greater than the south slope, the west slope is greater than the east slope, and the northwest slope is the largest. NDVI increases in steps with the slope increasing from 0 to 38.9°, but decreases sharply when the slope is higher than 38.9°. (3) In the flat land with the elevation less than 1 919 m and the slope less than 3.8°, the interannual increase rate of NDVI is small, and the significant degradation distribution is obvious. At elevations of 1 919-3 162 m, slope of 3.8°-25.1°, and aspects of northwest, west and north slope, NDVI is mainly stable and increasing, with high interannual variation rate. The vegetation transition area with elevation of 2 739-3 534 m, slope of 22.2°-28.0°, and slope aspect of east and west, where NDVI is prone to fluctuation, so it is necessary to pay attention and to strengthen ecological governance.