Abstract: The North Yellow Sea Basin is the only oil and gas-bearing basin, which does not form industrial oil-gas flow. The Eastern Depression is one of the most potential areas of the North Yellow Sea Basin,and the study of hydrocarbon geologic characters and structural evolution is the key to the exploration. Based on the analysis and researches of the former achievements and latest data, the hydrocarbon geologic characters and pool formation condition of Eastern Depression are advanced. In addition, three source-reservoir-cap rock assemblages are identified.Among them, late Jurassic source-reservoir-cap rock assemblage is the most potential one.