Abstract: In order to provide support for the territorial protection of our boundary river areas, the authors has taken the Yuanjiang-Honghe boundary river areas in China and Vietnam border as the study areas, and studied the soil erosion of the study areas by 3S technology in the study areas. Landsat 8 satellite remote sensing data and the soil erosion factors (normalized difference water index, vegetation coverage,soil erodibility and slope) were used to study the intensity of soil erosion. The remote sensing evaluation method about the intensity of soil erosion in the boundary river areas was preliminarily established. And some measures and suggestions for the territorial protection of our boundary river areas were put forward.