Report on Field Survey of Soil Erosion in Three-River-Source National Park Abstract: [Purpose] The Three-Rivers-Source region is located in the hinterland of the Qinghai-Tibetan Plateau, soil erosion types are complex and varied. Through the field investigation, we aim to comprehensively understand the characteristics of soil erosion in the region and to provide reference for soil erosion prevention and control in the region. [Methods] The investigation team travelled to Guoluo, Yushu, Hainan and Huangnan prefectures in three separate groups from 25 July to 20 August 2023. We have surveyed and analysed woodland, grassland, farmland, bare land, roads, river banks and mountain gullies in the above areas. [Results] The survey shows that the grassland has the most complex type of soil erosion, which is subjected to the joint action of multiple camp force erosion such as wind erosion, water erosion, freezing and thawing erosion and gravity erosion, resulting in its serious soil erosion. In addition, grassland damage by highland rodents may be another important factor in the occurrence of grassland erosion; The forestland has erosion gullies in the standing forest, but the overall risk of erosion is low due to the engineered slope protection; The foot of the slope on which the shrub land is situated is more exposed to hydraulic and gravitational erosion and is at greater risk of erosion; Farmland is spread over a small area, however, mild water erosion occurs in the field. For bare ground, fine gully erosion is more intense and soil erosion is serious. It is worth noting that on both sides of the road, the slopes are more severely eroded, and the excavation of the project has led to the destruction of the turf, sliding under gravity, and the emergence of larger exposed surfaces, which provide conditions for the occurrence of water erosion, leading to a larger network of erosion gullies that have already been formed in some areas. [Conclusion] Soil erosion in the Three-Rivers-Source region of Qinghai Province is complex and varied, with the intensification of human activities, risk of further exacerbation of soil erosion in localised areas. It is an urgent need to carry out soil and water conservation work in the new era, there is a need to strengthen the basic research on soil erosion in the region, strengthen the deployment of the network of soil and water conservation monitoring stations, intelligent management, etc. Keywords: Three-River-Source National Park; soil erosion; soil and water conservation; land use