[Objective] The interannual dynamic changes and causes of soil and water loss in the contiguous area of Shanxi, Shaanxi and Inner Mongolia during 1990-2020 was analyzed, in order to provide scientific support for the development of effective soil and water conservation in this area.[Methods] Based on the monitoring data of soil and water loss in 1999, 2018, 2019 and 2020, the interannual dynamic changes of soil and water loss in the study area were analyzed. By comparing the monitoring results in 2020 and 1999, the dynamic changes and their causes were analyzed.[Results] Due to the effective implementation of water and soil conservation guidelines, policies and measures formulated at the national and local government levels, the area of soil and water loss in the study area decreased from 4.71×10⁴ km² to 2.45×10⁴ km² during 1990-2020, reduced by 47.98%.[Conclusion] The intensity of soil and water loss in this area has been significantly decreased from strong and above erosion intensity to light and medium erosion intensity, and the ecological environment has been significantly improved. In the future, in accordance with the characteristics of regional soil erosion, further investment and more effective soil and water conservation measures should be implemented.