Abstract: The flowing characteristic of water film on wall is one of the main factors that influences the secondary droplets entrainment.This paper studies the flowing characteristic of water film on wall of certain sizes,using numerical method.Based on the analysis of water film surface forces,the dynamic boundary condition of water film free surface was obtained,and the wave flow models of water film on wall were es-tablished.The central-differencing algorithm was used for the continuity equation.And the blend of two-order upwind difference algorithm and central-differencing algorithm was used for the Momentum equation.SIM-PLE and VOF algorithm were used to solver the wave flow of water film on wall.Calculation results showed that the water file waved more acutely in the middle of wall than other places,and the inlet interferential fre-quency influenced the wave flow of water film more intensively than the inlet interferential.