Abstract: Some domestic oil fields have entered successively the subsequent water flooding stage after polymer flooding, and it is urgent to develop further EOR methods after polymer flooding. For this purpose, infilling well and combined EOR methods of S/P binary flooding after polymer flooding have been study through physical simulations. In the experiments, oil saturation changes in the physical models were measured by some oil saturation monitoring apparatus. The experiments indicate that there are still a large amount of remained reserves in the layers after polymer flooding and recovery factor can be further increased by 29.86% by infilling well and the combined EOR methods of S/P binary flooding.