[Objective] The objective of the study is to provide theoretical support for ecological restoration and sustainable management in the future by comprehensive assessment of eco-environmental vulnerability in Bailongjiang watershed in Southern Gansu Province. [Methods] Based on ecological sensitivity-resilience-pressure model and characteristics of eco-environmental systems in Bailongjiang watershed in Southern Gansu, we used analytic hierarchy process(AHP) method to assess eco-environmental vulnerability with GIS/RS technology. According to the eco-environmental vulnerability index, the study area was classified into five levels: slight vulnerability(<0.38), light vulnerability(0.38~0.44), moderate vulnerability(0.44~0.50), high vulnerability(0.50~0.57) and extreme vulnerability(>0.57). [Results] The moderately and highly vulnerable area accounted for 28.93% and 22.76% of the total area. Moreover, the highly and extremely vulnerable area was primarily distributed in the middle reaches of Bailongjiang watershed, which was characterized with low vegetation coverage, rapid urbanization and industry and agricultural development and frequent human activities. [Conclusion] The watershed is facing huge eco-environmental pressures. It is urgent to study the driving mechanism and evolution rules in order to provide support for ecological restoration and reconstruction in near future.