Abstract:There are several different views on the hydrocarbon accumulation process of the Changchunling Anticline in the northern Songliao Basin, such as oil source and oil and gas reservoir accumulation time. On the base of previous studies, from geochemistry, structure, sedimentation and hydrocarbon distribution, combining with thermal history and hydrocarbon generation history, hydrocarbon accumulation process is discussed in this paper. It is suggested that the oil of the Changchunling Anticline comes mainly from the first Member of the Qingshankou Formation, Lower Cretaceous, in the Wangfu Depression; natural gas is mainly from the deep coal bearing strata in the fault depressions on both sides; natural gas began to accumulate at about 85~77.4 Ma, the main accumulation period of oil reservoir is about from 75 to 67Ma. The gas reservoir formed earlier than the oil reservoir.