Abstract：Stochastic walk method is an effective method of modeling solute transport in fracture network. Traditional stochastic walk method locates new position of particle though given time step. However，it is difficult to define the size of time step. The size of time steps has an important effect on precision of simulation results. In this paper，traditional stochastic walk method is modified. In the condition of known spatial step，the analytical expression is developed between time and spatial steps. As a result，the size of time steps is expressed by spatial step automatically，which can avoid artificial factors in defining time step. At last，traditional stochastic walk method，analytical method and modified stochastic walk method are compared through a case study. Results show that solute transport in fracture network can be modeled efficiently based on modified stochastic walk method and that the modeling result is of relative high accuracy.
