【Objective】The Sichuan-Yunnan ecological barrier area is an important ecological function area in China. To reduce the increasing ecological degradation and soil erosion, it is important to research soil erosion and soil conservation functions. 【Method】The Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to characterize the spatial distribution of soil erosion and soil retention in 2000, 2010, 2015, and 2020. The GeoDetector was applied to detect the main controlling factors of soil erosion. 【Result】The results showed that the soil erosion modulus and the total amount of soil erosion in the four phases showed a trend of decreasing and then increasing. The erosion intensity was dominated by mild erosion, accounting for about 85% of the whole area, and mainly distributed in the eastern part of the area. The light and more than light erosion intensity were mostly distributed in the western part. Soil conservation modulus in 2000, 2010, 2015, and 2020 were 4.0×103, 3.5×103, 3.5×103, and 4.5×103 t?km-2, respectively, and soil conservation amount were 9.6×108, 8.3×108, 8.2×108, and 1.1×109 t, respectively. The influence degree of each influencing factor on soil erosion in descending order was as follows: land use type, elevation, fractional vegetation cover, soil erodibility, erosivity, and slope. The interaction effects between factors on soil erosion were greater than that single factor, and the interaction between land use type and soil erodibility had the strongest effects on soil erosion.【Conclusion】Although soil erosion in the Sichuan-Yunnan ecological barrier area shows a worsening trend, soil conservation is gradually improving, and soil conservation is stronger than soil erosion, and overall, the Sichuan-Yunnan area is developing in a better direction.