Abstract: There are various and abundant faultblock in Dagang oilfield with complex geological condition.Under this back-ground,carring on research on fault block lithofacies and pa-leogeography has very important meaning to locating more non-tectonic reservoirs.Qikou sag in Huanghua depression is secondary building unit.In an era of Paleogene,it went though the period of developing to extinction.Abundant li-thologic trap has been formed in the various geological period under Qikou sag unique lithofacies and paleogeography envi-ronment.In this article,Qikou sag unique lithofacies and paleogeography condition and the factors on which hthologic trap formed have been considered,Qikou sag coastal slope has been set as an example,the the probability of high-yield well in lithological trap developing area has been dis-cussed.