The suitable shrub-grass plants of Caragana korshinskii Kom.,Hippophae rhamnoides L.,Medicago sativa L.are the main research object.Soil moisture dynamic variation law of shrub-grass lands and the shrub in the closing area were studied by means of located observation and the harmonic analysis.Results show that the annual variation of soil moisture of the typical shrub-grass vegetation in the area affected by the annual variation of rainfall and evaportranspiration is remarkably divided into the arid and humid seasons,and four periods of soil moisture variation.The soil moisture profile is divided into the rapid change layer,the active layer and the second active layer by the two indexes of standard deviation and variation coefficient,and the relation of soil moisture profile with the precipitation in the same period is analysed.The adjusting function to soil moisture of shrub-grass lands,shrub forestlands is better than grasslands,farmlands and bare-lands,and the soil moisture condition of shrub in the closing area is better.The research results are important to the vegetation recovery and ecological engineering construction in a similar region.