In order to study the effect of different land use of saline-alkali soil on the soil salinization characteristics,the field investigation,sampling and indoor analysis were conducted. The morphological characteristics,soluble salt content,composition of salt ions,total alkalinity,pH,alkalinity and other indicators of soil profile were studied in six soil depths under five land use,namely,forest land,agricultural land,grassland,improved land and salt wasteland in Hetao plain. The results showed that there were significant differences in soil structure,color,root distribution,lime reaction and alkalinization of soil in different land use systems. The distribution of soluble salt and anion in soil profile was different due to different land use. Among them,grassland and forest land,were "olive",salt wasteland and improved land were "surface accumulation",and agricultural land was "bottom accumulation". The distribution characteristics of soil pH,alkalinity and total alkalinity in the profile were basically the same,showing an "S" pattern. The salinization degree and alkalinization degree of soil decreased with the different land use of saline-alkali soil,among which agricultural land was the most obvious. The total salinity,total pH alkalinity and ESP values of 0—20 cm soil decreased to 0.88 g/kg,7.83,0.17 cmol/kg and 12.54%,respectively,indicating that soda-saline and alkaline land was more conducive to soil desalination and dealkalization after agricultural use. Soil total salinity,Ca²⁺,Mg²⁺,SO₄^2-,total alkalinity and pH were the main factors of salinization in the studied area. These research results could provide technical reference for clarifying the salinization process and the improvement of salinized soil in Hetao plain.