Abstract: In the light of large amount of polymer in fluid produced by polymer flooding, which makes oil-water separation more difficult, the paper analyzes the characteristics of produced fluid containing polymer, and presents a chemical treatment technique for fluid produced by polymer flooding. Research results show that with the increasing of polymer concentration, the viscosity of the produced fluid increases, and the influence on dehydration, wastewater settlement, oil removal and speed of wastewater filtration become stronger, but on COD in the water after treatment is weak. Pretreatment agent KYYC-2 suitable for fluid produced by polymer flooding of Dagang Oilfield is selected and applied. Results display that when the concentration of KYYC-2 is 70 mg/L, after 6 hours, dehydration rate, water cut of purified crude oil, oil-bearing of wastewater and suspension content in wastewater all meet the needs of technical regulations.