Abstract: During high water cut stage,it is very difficult to develop the remaining oil in complex fault-block reservoirs due to its complicated distribution.In order to enhance recovery,this paper presents a method on tapping remaining oil by refining research unit into oil sand body.On the basis of fine geological research along with dynamic and test data,oil sand bodies are divided into elastic drive,injected water drive,injected water and edge water drive,edge water drive,and nonproducing types according to well pattern control conditions,features of water drive and edge water energy.Specific methods of tapping remaining oil for specific oil sand body types were advanced through dissection of producing status,remaining oil distribution pattern and potential of different oil sand bodies.The application in Yuejin II Oilfield shows that the method can effectively improve development of complex fault-block reservoirs in high water cut stage and provides new approach for tapping remaining oil.