In view of the large displacement production of marine sandstone FOURD reservoir, it is found that the water drive pore volume multiples at different locations are different during the development process of bottom water reservoir, while the experiments measured in the conventional industry standard are insufficient to express the seepage characteristics of the reservoir after the high flooding multiple. The high?power water drive experiment shows that the half logarithm of core displacement multiples with different clay content has a linear relationship with oil displacement efficiency, and the water drive sweep volume of bottom water reservoir increased slowly. Based on the actual data of FOURD reservoir, the time?varying characteristics of the reservoir were characterized and studied by numerical simulation technology. According to the different north?south dynamics of FOURD reservoir, the water flooding degree in the south area is high and the sweep degree is difficult to improve. The oil displacement efficiency of the reservoir is improved by liquid extraction, and in the north area and where the impact degree is not high, the later potential tapping mode of well network encryption is adopted. After adopting the limit tapping potential strategy described in this paper, according to the results of numerical simulation and practical mine application, the swept volume increased by 11.1%, and the calibration recovery increased by 4.5%.