Hydrological model can simulate the natural river basin of rainfall runoff process in rainfall runoff process, the selection of the hydrological model parameters tend to affect the model simulation results of the runoff process.According to Xin’anjiang model, taking heihe basin of Jinpen reservoir for the study watershed, the paper analyzed the impact of xin ''an jiang model parameters on the simulation of rainfall runoff process, so as to determine the sensitive of xin ''an jiang model parameters, which serve the study basin flood season hydrological forecast parameter correction.The simulation results show that in the research watershed, Xin’anjiang model parameters such as KKSS, KKG, WLM, WDM, kg, k are sensitive parameter, witch has greater influence on the rainfall runoff process of simulation; Parameters such as WUM, IMP, B, c, SM, EX are non-sensitive parameters witch have less impact on the rainfall runoff process of analog basin.