Abstract: China and the U.S.are the two largest consumer countries in the world.It benefited from the shale gas revolution in the U.S.in recent years，the oil self-sufficiency increases continuously.While the oil self-sufficiency rate of China has continuously dropped，the crude oil external dependence was increasing.Thus this paper makes a comparative analysis of the oil supply risk between the U.S.and China，aiming to identification of the oil supply risk point of China.Based on the energy security "4A" model proposed by the Asia Pacific Energy Research Center，we built up the risk evaluation model in the oil supply.The results show that China’s oil supply risk is generally higher than the US since 2000.China’s oil supply risk began to rise in a short period of 2000 to 2002，has been maintained at a high level.The oil supply risk of the U.S.began to decline significantly after 2008.China’s oil supply risk is mainly concentrated in the availability and accessibility，while the oil supply risk of the U.S.is concentrated in availability and acceptability.