Abstract: Equifinality is a difficult but unavoidable challenge in hydrologic modeling.A framework is established and presented to estimate the three baseflow parameters in the Variable Infiltration Capacity (VIC) model using soil properties.The new parameter estimation method is tested for streamflow simulations on three distinct catchments in hydro-climatic conditions in China.The simulations are compared to the previous calibrated results.The new method can reduce the number of VIC calibration parameters from six to three, thus decreasing model equifinality and uncertainty.The sensitivity of the calibrated parameters under the new framework is improved as demonstrated by the Monte Carlo simulations.The parameter uncertainty can also be reduced.In addition, the uncertainty of VIC simulations is assessed using the Generalised Likelihood Uncertainty Estimation (GLUE) method.Results show that the uncertainty of streamflow simulations (or, confidence interval) is low with the new parameter estimation method compared to the uncertainty resulted from the previous calibration method.The new method is applicable to the VIC model and other similar hydrologic models for streamflow simulations.