Abstrcat In loess hilly-gully region, there existing many types of soil, such as loessal soil, red clay, mantle rock soil, and so on. Based on observation and testing after planting different kinds of trees in loessal soil, red clay and mantle rock soil, the results showed that planting different trees can improve the physical properties of soil. Especially, planting Ippophae rhamnoides, locust, oriental arborvitae, poplar and mixed planted with these four trees are better than other trees. Mixed planting can accelerate the tree growing, as well as decrease soil water use effectively. And the soil porosity in mantle rock soil and the soil water content between 0-80 cm had increased, this showed that planted trees in mantle rock soil had certain potential, which is very significant for holding back the trend of soil and water loss in loess hilly-gully region