The use of new revetment structure of hydraulic flashboard permeable spur dike increases the benefits of flood control and revetment engineering at Xinjiang silt sand bed.In order to explore the influence of water permeability rate on scour prevention and sedimentation promotion effect of hydraulic flashboard permeable spur dike,the paper used movable-bed model test to study the change law of slow flow effect, local scour depth and maximum sedimentation height with water permeability rate so as to provide theory reference for the reasonable selection of engineering design parameters.The result showed that hydraulic flashboard permeable spur dike has a significant effect on reducing flow velocity after dam.The water permeability rate has less influence on velocity of flow behind dam. The maximum scour depth deceases with the increase of water permeability rate. The maximum sedimentation height of dam firstly increases and then decreases along with the increase of water permeability rate.When water permeability rate is 30 percent, the scour prevention and sedimentation promotion effect of the dam gets the best.