Abstract: In order to enhance recovery ratio carbonate of buried hill reservoir in Renqiu,a comprehensive research on ge- ology,logging,geophysical prospecting and reservoir en- gineering has been carried out in this paper.It is proposed that the geometric shape of top bed,distribution of interi- or aquifuges and developing degree of fractures in buried hill are the main geological factors for controlling the dis- tribution of remaining oil in the reservoir.Through apply- ing various new technologies and methods comprehensive- ly,the above geological factors are described accurately. The patterns of remaining oil distribution controlled by various factors are classified into six main types and nine subtypes.At the same time,this paper points out the re- maining oil controlled by interior aquifuges and fractures network are the favorite potential regions in the future.