The offshore polymer flooding reservoirs are mostly in the middle and late stages of oilfield development, and there are multi-well systems. At present, most of the well testing methods for polymer flooding reservoirs are based on single well system, which leads to the fact that the actual data fitting effect is not ideal. By considering the influence of adjacent production well or polymer injection well and the physical and chemical effects of polymer solution such as shear, diffusion and convection, the well test interpretation method of polymer injection well considering adjacent well interference is established, type curves were plotted and its influencing factors were discussed by the numerical inversion method. The result showed that the type curves have five regimes, the pressure derivative curves show obvious upward warping under interference from production well, while the pressure derivative curves first decrease and then continue to rise under interference from polymer injection wells. Polymer injection well test curves show obvious non-Newtonian fluid characteristics when considering adjacent well interference, and can not be analyzed by conventional adjacent well interference test method. The example application proves the correctness and reliability of this method, which provides a theoretical basis for dynamic adjustment of polymer flooding reservoir.