From the samples collected in field, in Xizhaogou wa tershed in Inner Mongolia, China in 2005.Soil organic matter content is measured in laboratory.The result indicated that the soil organic matter content in the gully with seabuckthorn flexible dam is much higher than that without the flexible dam.The flexible dam has the notable ecological effects of improving soil organic matter content and soil fertility in gully.At the same time, the result shows that soil organic matter content has a certain vertical variation, but the maximal value occurs in the surface soil layer in most cases.Soil organic matter content increases gradually from upstream to downstream in the gully with seabuckthorn flexible dams and in the dam body.This change is similar to the longitudinal change of sediment thickness in the gully with dams.