Abstract: The result from the investigation and analysis of the evaluation on two fixed experimental sites in Shuangbai and Jindian shows that the planting of Eucalyptus, Acaccia mearnsii and their mixed forests can not only quicken soil development, slow down soil leaching, soil bulk density, improve soil porosity and increase soil water storage.But Eucalyptus has more obvious effect on the mentioned aspects.It can better the physical properties of soil in severe soil erosion area in the central part of Yunnan and, therefore, promote the development of forestry.