The Paleogene Shahejie Formation (Es) is the most important hydrocarbon accumulation combination in the Dongying depression. On the basis of former researches, the authors collected more than 600 source rock samples and 186 oil samples from 30 oil fields, and carried our organic geochemical testing. According to the combining sedimentary sequences and geochemical analyses, the source rock of the Shahejie Formation can be divided into three genetic models, including saline lake facies (upper Es 4), semi-saline deep lake facies (lower Es 3) and fresh lake facies (middle Es 3), corresponding to under-filled, balance-filled and over-filled lacustrine types respectively. Furthermore, there is intense heterogeneity in the source rock of the Shahejie Formation, particularly in the balance-filling process. This heterogeneity is closely related to the change of lake level. According to this relationship, the authors proposed fluctuating lake-facies sedimentation. Oil-source correlation shows that source rocks from saline and semi-saline lake facies are the main source rock in the Dongying depression. Finally, the authors discussed the occurrence of organic matter and the manner of petroleum migration, and pointed out that oil generating from saline lake facies source rock migrated laterally and accumulated on the margin of the basin, but oil from semi-saline lake facies source rock migrated vertically and accumulated around the center of the basin.