Abstract: The capacity of water-retention and-supply for plants of the soils on five typical vegetations were analyzed by measuring the soil water characteristic curves and physical properties in the north side of Liupan Mountains,Ningxia.The results showed that the relationship between soil moisture and soil suction could be successfully expressed by the power function proposed by Gardner et al.(1970).The soil density in different layers on five vegetations were ranged from high to low values as follow: abandoned land,Prunus davidiana plantation,Stipa bungcana community,Larix principi-rupprechtii plantation and Hippophae rhamnoides community.However,the order of total soil capillary porosity of the five vegetations was just contrary.From 0.1 to 1.5 MPa in soil suction,soil water content of Larix principi-rupprechtii plantation,Stipa bungcana community,Hippophae rhamnoides community, Prunus davidiana plantation and abandoned land were ranged in 169.7～239.3 g·kg-1,160.3～236.1 g·kg-1,140.9～224.5 g·kg-1,119.9～198.1 g·kg-1and 113.5～176.4 g·kg-1 respectively,it meant that the soil capacity of water-retention of the five vegetations decreased in order.The order of soil capacity of water-supply for the five vegetation types was the same as soil capacity of water-retention,and it decreased with increasing of soil suction.The results could be explained by the positive effect of soil physical properties(i.e.soil density and total capillary porosity et al.) caused by planting trees and grass on the soil capacities of water-retention and-supply.