In the process of offshore chemical drive, water drive well network and polydrive well network coexist after well network densification, which exerts a deep influence on oil development. To quantitatively characterize the perturbation degree of injected water and polymer, a water-polymer perturbation coefficient considering the dynamic changes of displacement volume of injected water and polymer is proposed. The production characteristics and laws under different displacement modes are analyzed based on the water-polymer perturbation coefficient, and the control strategies are discussed.The results show that the injected water would compress the polymer displacement area and exert an interference on the polymer front edge. Water-polymer perturbation coefficient has a good correlation with stage net oil increase curve, and water-polymer co-flooding process can be divided into five stages according to the water-polymer perturbation coefficient. In addition, water-polymer co-flooding has a better oil production than pure polymer flooding at the initial stage, but for a long period, development effect of pure polymer flooding is much better, and water-polymer alternating injection can balance the displacement front and improve the development effect. The result has a great significance to quantitatively characterize water-polymer perturbation degree and make adjustment measurements.