Abstract: Dongying Formation is characterized by steep-dip structure, narrow oil-bearing area and high net-to-gross in 5&6 well blocks, JX oilfield, being typical thick sandstone reservoir in slope break belt. Through palaeo-geomorphology restoration and stable horizon marker selection, the constrained framework for stratigraphic correlation has been established. Using well log and drilling core data, sedimentary cycle division and multi-well stratigraphic correlation have been finished, and the fine stratigraphic correlation framework has been constructed for 5&6 well block in JX oilfield. The result of stratigraphic correlation has been examined through fault point identification, well-seism calibration and oil/water interface analysis. Nine oil layers have been divided finally. Based on the result of stratigraphic correlation, combined with reservoir simulation results, Dongying Formation is divided into seven development layer serieses. The development method of production oil on high position and injecting water on low position has been used, and good oilfield development effect has been obtained.