The Dongying Formation in the Chengbei Sag of Bohai Bay Basin was studied to understand its structural features and how they relate to hydrocarbon accumulation. The Chengbei fault and its branches controlled the distribution of oil migration, with the southwestern gentle slope and northeastern steep slope being key areas for hydrocarbon accumulation. Faults in the inner sag and southern slope are less likely to form traps. The combination of structure and sediment plays a crucial role in hydrocarbon accumulation in the Dongying Formation, with potential for exploration in structure-controlled reservoirs in the northern fault zone and stratigraphic reservoirs in the southern gentle slope zone.