The paleolandform of the pre Jurassic was reconstructed by the method of mold. The research shows that the paleomorphic units in the study area includes three slopes,three river valleys,two mounds and one ridge,i.e.,the East Jiyuan slope,Dingbian slope and Jingbian slope ; the Ganshaan river valley, Ningshan river valley and Mengshan river valley;the Wuqi mound and Jinding mound; and the Xinanbian ridge. The early deposition of Yanan Formation is controlled by the prejurassic paleolandform. In the period of Yan 10 deposition,the facies mainly belong to fluvial deposition,and the microfacies are mostly primary channel,distributary channels,overbank deposit and overbank swamps. In the period of Yan 9 deposition,the sedimentary environment is deltalacustrine,the subfacies are mostly delta plain and delta front, and the microfacies are distributary channels,interchannel depressions,underwater channels and interchannel bays. The shapes of reservoir sandbodies and distribution patterns are bound to change with  the different sedimentary environments in the same paleolandform units,and make great influence on the formation and distribution of the oil reservoirs. The formation of paleolandform oil reservoirs is mostly restricted by the source of the oil and traps. The paleogeomorphic sedimentary combination and migration channels also the are major conditions of forming different types of paleogeomorphic reservoirs. Three paleogeomorphic reservoir models ie. the slopedelta plain combination,mounddelta front combination and combination of slopedelta front.have been generalized in DingbianWuqi area on the basis of the  distribution of the oilfields,the paleolandforms,the deposition environment of overlying formation, sandbody distribution,migration channels