For the widespread problem of soil salinization in arid zone,the paper took the lower reaches of Tarim river basin as research area and studied the spatial variation of soil salinity at different levels by use of the method of combining classical statistics and geo statistics. At the same time,it discussed the influence factors of soil salinity and its variation law by use of the data of groundwater depth and salinity at typical section from 2000 to 2011.The results showed the accumulation was manifest on the surface, the accumulation effect of soil salinity is obvious and there is a significant correlation in space.The effect decreases gradually from top to bottom in vertical direction and maintains integral strip in the horizontal direction and the variation characteristics of local patch pattern The groundwater depth and salinity is the major factor which impacts distribution of soil salinity.There is a good exponential function between soil whole salt with groundwater depth and salinity. The inter-annual variability of groundwater depth and salinity, indirectly reflected the trend of soil salinity,which can provide theoretical basis and scientific basis for soil salinity control and regulation of regional water and salt movement in the study area.