Based on two years of continuous located observation of soil moisture of Salix psammophila and Caragana korshinskii woodland with different site conditions in Yanchi,Ningxia province,this paper discusses the spatiotemporal dynamic change of soil water content and soil moisture characteristics of sandy land grown on different parts of sandy region and different site conditions.The results showed that Caragana korshinskii woodland have the lowest soil bulk density,but the highest water retention capacity.Water distribution along soil profile different research samples showed obvious layered features,there are three layers:low-level layer,active layer and stable layer,and the thickness of each layer is different because of different site conditions.