Abstract: With the rapid development of social economy, most of the river basins in China have been affected by human activities, resulting in a series of problems such as water pollution and biodiversity degradation. The ecological health of river basin ecosystem has become one of the prominent factors restricting the sustainable development of China's economy and society. Therefore, it is of great significance to carry out the risk analysis of the impact of human activities on ecological health. It will also play an important role in the decision-making guidance of the future watershed ecological environment protection and construction in China. This study has established an index system including human activities, ecological pattern, ecological function and ecological pressure contents. Combined with interactive risk assessment matrix, the risk of the impact of human activities on ecological health based on watershed scale has been analyzed. The results show that: (1) The GDP and population of the Hulun Lake Basin are mainly distributed around Hailar District and Manzhouli City, while the GDP intensity and population intensity of other regions are relatively low. (2) The GDP intensity index of the Hulun Lake Basin has two sub basins in the medium and high state, respectively; the population intensity index has one sub basin in the high state, two sub basins in the medium state, and the ecological health index has eight sub basins. (3) Among the 32 sub watersheds in the Hulun Lake Basin, 30 sub watersheds are in low-risk state, accounting for 98.62% of the whole region, and the other 2 sub watersheds are in medium risk state, accounting for 1.38% of the whole basin. There is no high-risk sub watershed in the study area. Furthermore, the assessment method proposed in this study can effectively assess the risk of the impact of human activities on the ecological health, so as to provide theoretical basis and technical support for the ecological environment protection and sustainable development of the basin.