In order to explore the effects of species configuration measures on the nature of soil hydrology in the project of conversion of cropland to forest land,soil porosity and the capacity of water-holding for 10-year-old Robinia p seudoacacia,Platycladus orientalis,and Pinus tabulaef ormis are determined using forest ring in the loss hilly region.Results show that (1) a variety of stands have significantly improved the capacityof water-holding,i.e.,the performance to reduce soil bulk density and increase soil porosity and soil water-holding.The greatest improvement is by Robinia pseudoacacia,the second is by Pinus tabulaef ormis stand,and the third is by Platycladus orientalis.(2) Increase in the amount of residual water of soil( non-capillary porosity) by various stands is greater than the degree of(capillary porosity) water retention.(3) The vertical spatial variability of forest soil is obvious.With the increase in soil depth,soil bulk density is increased,but soil porosity and water storage are reduced.