Numerical simulation is of great importance as implementation guides of polymer flooding projects. However，there are still significant difficulties remaining in the history matching process of polymer flooding simulation due to uncertainties of some related parameters in polymer flooding. Based on laboratory experiments of polymer core-flooding，the reservoir simulation parameters for polymer flooding were determined by curve matching of water cut and oil recovery. A more reliable numerical simulation model of polymer core-flooding was then constructed. The effect of viscosity of polymer solutions，inaccessible pore volume，residual resistance coefficient and polymer adsorptive capacity and other related parameters on curves of water cut and oil recovery were analyzed. The sensitive coefficient was introduced in the model to evaluate the sensitivities of these parameters. Results show that the sensitivity order of different parameters to the increase rate of oil recovery and the decline rate of water cut is consistent. The sensitivity of these parameters from strong to weak is：polymer adsorptive capacity，viscosity of polymer solutions，residual resistance coefficient and inaccessible pore volume.