Abstract: Taking the Lower Member of Guantao Formation in Tanhai area, Shengli Oilfield for example, the syn-sedimentary faults in different blocks are studied according to the logging, seismic and core data. It is found that the sedimentary differences between the two walls of faults are related to the active intensity of syn-sedimentary faults and supply rate of sediments, and the relationship between fault strike and river mainstream direction as well. Based on further research, two cases of sandbody controlling model are summarized as follows:When the fault is perpendicular to flow direction, due to small space in upthrown side, the sandstone is cut and overlaid, dominated with large blocks of sand. The mudstone is difficult to preserve, thus the percentage of sandstone is high. While the sandstone on downthrown side is mostly isolated and in thick single-layer, but the mudstone is more developed. Therefore the sandstone is in low percent. When the fault is parallel to flow direction, the sandstone on upthrown side is less and thin with low percentage; while that on downthrown side is more and thicker with high percentage.