Abstract: Organosilicon functional fertilizer and saline-alkali soil were used as experimental materials.Nine treatments were set up, including no modifier（CK）,application depth 5 cm（W5）,10 cm（W10）,15 cm（W15）,20 cm（W20）,surface layer application（W-0）,layer application position 5 cm（W-5）,10 cm（W-10）,15 cm（W-15）.The effects of application depth and position of organosilicon functional fertilizer application on soil water transport and soil change were studied, in order to provide reference for the use of organosilicon functional fertilizer and the improvement of saline-alkali land.The results showed that the depth and location of organosilicon functional fertilizer had effects on soil water infiltration characteristics.With the increase of penetration depth, the migration distance of wetting front and the cumulative infiltration amount decrease.The closer the layer application location was to the surface of the soil column, the cumulative infiltration amount and the migration distance of wetting front decrease obviously.With the extension of infiltration time, the cumulative infiltration amount and the migration distance of wetting front between different treatments would be equal at a certain moment.Organosilicon functional fertilizer increased soil water content, and the effect of application depth on soil water content was more obvious than that of layer application.Organosilicon functional fertilizer could reduce soil salt content.In the depth of the soil layer containing organosilicon functional fertilizer, the electrical conductivity was significantly lower than that of the control.The deeper the application depth was, the lower the electrical conductivity was.In the depth of the soil layer without organosilicon functional fertilizer, the electrical conductivity increased significantly.Around the layer application site, the organosilicon functional fertilizer made the soil salinity appear the minimum value, and the electrical conductivity of other soil layer sites was higher.