The plane heterogeneity of S offshore Oilfield is strong. After years of polymer flooding development，areal drainage degrees are heterogeneous，and the effect of water-controlling and oil-increasing is weakened. In particular，the remaining oil distribution after the polymer flooding is complex，so the development effect of oilfield needs to be further improved by optimizing injection-production pattern. According to the relationship between the distribution characteristics of sedimentary facies and well pattern in S Oilfield，the plane heterogeneous conceptual models from the high，medium and low permeability zones are established. Based on the above models，a physical simulation model with the plane permeability ratio of 3 is established. Five groups physical simulation experiments of different well spacing are carried out under the same injection-production conditions. Then the reservoir geological models corresponding to the laboratory physical models at five permeability ratios are established by using the reservoir numerical simulation. Eight simulation schemes of well spacing are designed for each geological model，so that the total number of simulation schemes of well spacing are equal to 40.The experiment results show that when the plane permeability ratio is 3，the cumulative oil production is the highest when the ratio of well spacing is 1.8. And pressure gradients in the low and high permeability reservoirs are basically the same，so microelectrode saturation test shows that the low permeability layer and the high permeability layer are both produced effectively. Through deeper analysis of reservoir simulation results，the optimal well spacing under different plane permeability ratios is obtained. The optimal well spacing ratio gradually increases with the increase of plane permeability ratio. Finally，based on the optimal results，it is concluded that horizontal injection well and vertical production well form the best well pattern through the physical simulation experiment and reservoir numerical simulation.