Abstract: Based on the new 3D data of the east of Sandaoqiao area, the fault characteristics of pre Mesozoic buried hill in the north of Shaya uplift was analyzed. Combined with the regional tectonic background, the formation stages of faults were analyzed, and meantime the petroleum geological significance of different faults was studied. The results show that reverse faults, normal faults and strike slip faults were developed in the pre Mesozoic buried hill of northern Shaya uplift, and there were three groups of strike in plane, namely NNE, NW and EW. The strike slip fault to the south of Luntai fault was formed in the middle and late Caledonian period. The strike slip fault to the north of Luntai fault was reformed by Hercynian reverse fault. It has the characteristics of "apparent reverse and real positive" on the profile, and presents NE direction on the plane. The NNE trending reverse faults were formed in the late Caledonian and early Hercynian movements, and were shaped in the late Hercynian movement. The NW trending normal fault is related to the Permian volcanic activity in the late Hercynian. The nearly EW trending thrust fault was formed in the late Hercynian movement and Indosinian movement. The faults with different properties and stages have constructive significance for the formation of buried hill traps. The reverse fault controls the formation of fault structural belt, forming anticline, fault anticline, fault block and other structural traps. The extensional faults and strike slip faults related to volcanic rocks can effectively improve the reservoir conditions of carbonate rocks.