Abstract: Based on the exploration results and geological cognition obtained in the northern margin of the Qaidam Basin,the major controlling factors of hydrocarbon accumulation in this area were discussed in depth and the distribution rules of hydrocarbon were analyzed systematically.This has an important significance for refe rence in the petroleum exploration of this area.It was pointed out that the distribution of hydrocarbon in the northern margin of the Qaidam Basin mainly follows four rules.The distribution of effective surce rocks is the precondition to the discovery of hydrocarbon,the thermal evolutionary degree of source rocks determines the resource types of oil and gas fields,the paleotraps formed by the Early Himalayan movement at the end of the Eocene match well with hydrocarbon-generating history,and the shallow strike faults formed since the third episode of the Himalayan movement have greater katogene to primary oil pools.