[Objective] To study the characteristics of soil salinization and the distribution of soil salt ions in Yaoba Oasis of Alax Left Banner in Inner Mongolia Autonomous Region, and to provide a certain basis for the development of agricultural production and ecological environment protection.[Methods] We studied the distribution of soil salinization, the relationship between ion content and values of total alkalinity, salt ion content, as well as the relationship between salt amount and ion content by the means of sampling, GPS positioning and statistical methods. The testing results were analyzed with Excel software and SPSS software.[Results] The average pH value of the irrigation area soil is 8.13, it is alkaline soil. Land of Yaoba Oasis is high in salt content. The salt content of soil is mostly concentrate in 0-10 cm depth, which can reach 4.49%. Cations are mainly Ca²⁺ and K⁺+Na⁺, whereas anions are mainly SO₄^2-, Cl^-, HCO₃^- in the study area, having a rank as:SO₄^2- > Cl^- > HCO₃^-. Content of CO₃^2- accounts for few proportion. There are significant positive correlations between SO₄^2- and Ca²⁺ both in 0-10 cm soil layer and 10-60 cm soil layer, and their correlation coefficients are more than 0.95. Factor analysis showed that there are significant ties between SO₄^2- and Ca²⁺, and between anion Cl^- and cations of K⁺+Na⁺.[Conclusion] The salinized soils in the irrigation area are mainly sulphate and chloride saline soils, which are harmful to the growth of vegetation.