Pisha sandstone area is one of the most serious soil erosion areas in China. In order to study the influencing factors of the soil denudation rate and the improving effect of W-OH material on the Pisha sandstone slope, the Pisha sandstone from Zhungeer banner of Inner Mongolia Autonomous Region was used and the effect of the erosion discharge (2, 3 and 4 L / min), slope angle (5°, 7.5° and 10°) and the W-OH spraying concentration (1%, 2% and 3%) on the soil denudation rate and microstructure of Pisha sandstone slope surface were studied by the method of simulated scouring experiment. The results show that: (1) The denudation rate of Pisha sandstone slope decreases gradually along the slope direction (from the top to the bottom), and it increases with the increase of flow and slope angle; (2) When the slope angle and flow are fixed, the denudation rate is improved significantly with the increase of the spraying concentration of W-OH solution. When the concentration is more than 2%, the consolidation effect of slope is more obvious; (3) SEM results show that W-OH solution can effectively wrap the Pisha sandstone particles to protect them from erosion, and the soil anti-scouribility is increased. Additionally, it is closely related to the concentration of solution and the amount of spray, and also to the slope angle and the flow. The research results will provide some theoretical support for the application of W-OH material in Pisha sandstone area.