Abstract: As conventional method to calculate the exchange volume between surface water and groundwater,a calculation area was identified by a tessellation polygon surrounding an observation wells,in which obtained parameters of penetration was encompassed applying centralized models or low-distributed models.Based on the uncertainty of parameters,we presented an innovative calculation method to calculate the exact exchange volume between surface water and groundwater in this paper with applying numerical simulation and D8 arithmetic.The method counted the variability of seep direction combined the fluctuations of surface water and groundwater,and assumed the distribution modeling of hydraulic conductivity complying logarithm normal distribution.Therefore,exchange volume was calculated using innovation calculation method and compared with calculation result using conventional method.It was revealed that the seepage flow direction varied significantly accompanying with the fluctuations of water level and groundwater table.