Abstract: 【Objective】 Land quality and the safety of agricultural products are essentia-l for human health.The purpose of our study were to comprehensively reflect the actual pollution condition of the surface soil by heavy metals in arid areas and to reveal the pos-sible ecological risks of farmland soil in Midong area. 【Method】 In this study， sampled surface soil and analyzed the content of As， Cd， Cr， Hg， Pb， Cu， Zn and Ni， utilizeded the Geoaccumulation Index and the Potential ecological harm index method to evaluate the ecological risk in this region， correlation analysis and principal component analysis were used to explore the main sources of heavy metals in the soil of Midong region. 【Result】 The levels of 8 heavy metals in the farmlands of Midong area were lower than the limits of Farmland and Environmental Quality Evalluation Stands for Edible Agricultural Produc-ts（HJ/T 332-2006）.The average values of Cd， Hg， Cu and Zn were all exceeded Xinjiang background values， and the mean contents of Cd and Hg were 3~4 times of the backgro-und values.The average I_geo values were in the following order: Hg>Pb>Cd>Zn>Cu>Ni>Cr>As.The 7 heavy metal elements of Midong district were light pollution. The average value of ec-ological hazard index (RI) was 31.41， it evaluated that the midong district was all in low potential ecological risk.The main sources of Cr a-nd Ni in Midong regioon's soil were natural sources，the main sources of Hg were anthrop-ogenic sources， and the main so-urces of Pb， Zn， As， Cd and Cu were natural and anthr-opogenic combined sources. 【Conclusion】 Heavy metals in farmland soils in the Midong a-rea were slightly polluted and had a low potential ecological risk， and it still belong to t-he production safety area.