Abstract: Spatial variability causes uneven soil moisture distribution in the arid area. Soil moisture has an important influence on the interaction among the hydrosphere，the biosphere and the atmosphere，and the precipitation is less and the soil moisture is one of the important factors to maintain the growth of vegetation. In order to analyze the spatial variability of soil moisture and its distribution trend in different seasons and at different soil depths based on the measured data of moisture in the rub of field test and Yutian Oasis，Xinjiang，China taken as the study zone，the geo-statistics combined with GIS was applied to analyze the spatio-temporal variability of the soil moisture content. Soil moisture content measurements were performed biweekly at six depths in soil profile （0-10，10-20，20-40，40-60，60-80，80-100 cm） from April to October. The results shows that Yutian Oasis soil moisture content has a seasonal pattern，the spring average soil moisture is 0.139%，the summer is 0.110%，and the autumn is 0.123%. In the vertical distribution，the soil moisture shows a gradually increasing trend with soil depth increasing. In all seasons，the spatial autocorrelation of soil moisture content at different depths shows a similar trend，with strong spatial autocorrelation as the spatial unit is 1. Human activities are the dominant affect factors. In the study area，soil moisture has significant spatial variability，while spatial correlation is weak; soil water content inside the oasis is higher than that outside the oasis significantly.

Key words: soil moisture, variogram analysis, geo-statistical analysis, Kriging method, the Yutian Oasis