After the long-term water flooding,the oil reservoirs in the ultra-high water cut stage have unbalanced displacement in the plane and vertical direction,which affects their development effect. In order to achieve the equilibrium displacement,a numerical simulation technique was proposed to quantitatively characterize the displacement multiple and identify the difference in the displacement degree at different positions of the reservoir. According to the relationship among displacement multiple,residual oil saturation,and percentage recovery of OOIP,the displacement multiple was graded and evaluated. The ultra-high water cut reservoir was divided into four zones:weak displacement zone,strong displacement zone,high water consumption zone,and ineffective water injection zone. The distribution pattern of displacement multiple in different zones was determined,basis on this,the strategies for improving the displacement multiple of the weak displacement zone,changing the direction of liquid flow in the strong displacement zone,controlling the high water consumption zone by injection and production,and restraining and regulating the ineffective water injection were formed. The well pattern adjustment and optimization scheme of theⅧ-Ⅸoil zones in Shuanghe Oilfield was proposed. After the implementation,the waterflood recovery factor was increased by 1.43%,which achieved good application results.