It is increasingly general to apply geographic information system in precess of planning soil and water conservation, But it still needs more study to use this new technique better.Taking Liuyie gully small watershed for an example, the author discusses the problems about how to plan soil and water conservation at small watershed with GIS.to make the program more canonical.scientifical and modernistic.and more fit for the characteristics and the needs of soil and water conservation.People then can get to the best objective of economical, ecological and social benefits.