Abstract: Hu 7 Block has been at high water content stage, and oil field development is becoming more and more difficult. So it is very important to search for the regions with rich remaining oil. In this article, the distribution regularity of the remaining oil in north of Hu 7 Block has been summarized under the guidance of sedimentology theory, structural geology, oil recovery engineering on the basis of existing well pattern. Through study it is found that the enrichment patterns of the remaining oil is divided into two types, one is enriched in the edge of structure and the high position of micro structures which can't be flooded by injected water. The other one is enriched in the layers with low permeability. By deployed new wells, side drilling old wells, taking oil wells converted to water wells, optimization of wells spacing and well patterns, selecting pulse injection and using the technology of oil production engineer-ing to, water flooding efficiency has been improved greatly. By using fracturing technology, the physical properties of reservoirs have been improved. It is hoped that the oil reservoir could keep stability, and oil field development can be economic and efficient.