Abstract: In recent years, the relations between crude oil pipeline construction and environmental protection have attracted more attention than before.To fully evaluate the environmental risk level of Lancangjiang River Overhead Crossing Project of China-Burma Crude Oil Pipeline, this paper carries out a quantitative evaluation on environmental risk of the Lancangjiang River overhead crossing pipe bridge of the Pipeline with environmental background investigation, environmental risk identification, environmental consequence simulation, and other means by referring to the theories and methods for crude oil pipeline risk evaluation at home and broad. The results show that the leakage of pipeline will cause more serious impact on the coastal animals and plants and water quality of the Lancangjiang River, but the impact time is shorter,so it is not permanent or catastrophic; the crude oil leakage will not cause impact on the countries downstream of the Lancangjiang River including Burma, etc., The environmental risk in Lancangjiang River Overhead Crossing of China-Burma Crude Oil Pipeline is within acceptable ranges. This environmental risk evaluation realizes a beneficial exploration for the quantitative evaluation of environmental impact of crude oil pipeline overhead crossings over an international river.