In order to study the influence of salt in the dustfall on the statue surface on the water migration in the earthen layer, this paper compared the relationship between the moisture content, electrical conductivity, and soluble salt content (Cl−, SO4 2−, K+ and Na+) with the sample height of the soil in the coarse-fine mud and the soil before-after desalination, after the migration of the simulated earthen test block under different relative humidity stabilizes. The result shows: When the dustfall salt migrate to the earthen layer, its salinity will migrate downward at the upper end of the test block; When the interaction between the dustfall salt and the water of the earthen layer, the electric conductivity and soluble salt content in the test block are increase with the increase of sample height, and quickly increase above the test block 6.7cm; The effect of coarse- fine mud layer on electrical conductivity and ion content is not significant, and the electric conductivity and soluble salt content in the test block containing salt were obviously higher than those in the desalted test block. Overall, the dustfall salt, as exotic salinity, plays a certain role in promoting the production of salt damage in the statue and promotes the ability of the water-salt transport in the earthen layer which will aggravate the corrosion of the statue surface.