The severity of soil and water loss in the Loess Plateau is on the top in the world.It has an important significance to apply "3S "techniques in the practice and research of dynamic monitoring of soil and water conservation in the Loess Plateau.The research shows that soil and water conservation monitoring on a relatively larger area should be implemented in macro,micro and in-between scale,and a combination of satellite remote sensing,plane remote sensing and GPS should be adopted.In the aspect of macro monitoring,it is recommended to adopt middle resolution to monitor the intensity,area and developing tendency of soil and water losses.With regards to the dynamic monitoring of soil and water loss and the soil and water conservation measures,plane remote sensing or satellite image with high resolution is recommended on in-between scale.The monitoring on the change of geo-morphology,such as the advance of the heads of the gullies,the gully's expanding vertically and horizontally,should be implemented on micro scale by applying GPS technique to get information of soil erosion.