Abstract: In order to explore the water permeability effect, soil preservation and anti-silting performance of subsurface drainage pipes under different conditions of outsourced filter material, five types of subsurface drainage pipe outsourced filter material schemes were set up, namely sand filter material（A）, 68 g/m2 geotextile（B）, 90 g/m~2 geotextile（C）, 68 g/m~2 geotextile + sand filter material（D）, and no outsourced filter material（E） scheme as a control.Through the indoor penetration test, the monitoring and investigation of spring irrigation and autumn watering in the field, the influence of different filter materials on the water permeability, soil preservation and anti-silting performance of the subsurface drainage pipe were comprehensively analyzed.The results show that the attenuation rate of the drainage flow of scheme A, B and D was stable at 5.60% on average, and the attenuation rate of scheme C was 11.15%, second only to scheme E（15.094%）.The permeability coefficient of different filter media in the stable state ranged from 7.46×10^-4 cm/s to 9.46×10^-4 cm/s, and GR≤3;Compared with spring irrigation, the soil loss of each scheme in autumn was reduced by 42% on average, and the soil loss attenuation rate of scheme D was only 35%, which was lower than other schemes（P ＜ 0.05）.At the same time, the soil loss d90 of scheme A to D was 14.8, 18.50, 9.0 and 15.50 μm, respectively, and the soil preservation performance was significant compared with scheme E（d90=23.33 μm）;The amount of silted soil in scheme B, C and D was 12.54, 17.64 and 7.00 g, respectively, and the amount of silt in scheme D was significantly lower than that in other schemes where only geotextile is laid, indicating that scheme D has the best anti-silting effect.In summary, according to the soil properties of the downstream of Hetao irrigation area, it is recommended to preferentially select scheme D（68 g/m~2 geotextile + sand filter material） as the filter material for subsurface drainage pipes in the irrigation area.The research results can provide a reference for selecting suitable filter material for subsurface drainage pipes in the downstream of Hetao irrigation area.