Abstract: In order to further enhance the technical and profit potential of hydrophobically associating polymer flooding in J3 well area of Bohai oilfield, formulary lab experiments and pilot field tests were conducted. On the basis of those tests, a commercial chemistry flooding simulating software, FAPMS, was used to analyze the effect of the following parameters, such as the size and the concentration of high concentration polymer prepositive segment and main segment, as well as the combination style of segments, on the oil displacement efficiency. Furthermore, the injection procedure and segment size of field polymer flooding test were optimized in J3 well area of Bohai oilfield. The result shows that the optimization on the hydrophobically associating polymer flooding could lead to a 10% improvement in oil recovery ratio. The study shows that enough emphasis should be put on the optimization design of the polymer injection procedure and segment combination, to improve the technical and profit potential of polymer flooding.