Abstract: 【Objective】 The study aimed to analyze the contents of eight kinds of heavy metals（i. e.,Cd,Pb,Cu,Cr,As,Hg,Zn and Ni） in farmland soil of Dingbian County.【Method】 Single-factor pollution index method,Nemero comprehensive pollution index method and potential ecological risk index method were used to evaluate the soil,and both correlation analysis and principal component analysis were utilized to determine the sources of heavy metals.【Result】 The spatial distribution of the eight heavy metal elements was asymmetrical and unbalanced,with Hg and Cu concentrated and the rest of the elements unconcentrated. Based on the background value,Hg was at the clean and safe level,Cd,As,Cu,Ni and Zn were at mild pollution level,and Pb and Cr were at severe pollution level. The potential ecological damage index ranged from 1. 074 to 40. 677,which belonged to the level of slight and moderate damage. Based on the risk screening value of soil pollution in agricultural land,the content of heavy metals in farmland soil of Dingbian County was at the clean,safe,and slightly ecological hazard level. Through correlation analysis and principal component analysis for soil heavy metals,it was preliminarily determined that Cd,As,Pb,Cu,Ni,and Zn had the mixed sources of agriculture,transportation,and coal burning. Cr had the source of pollution by oil and gas exploitation,and Hg had the natural source.【Conclusion】 The soil in the studied area is suitable for agricultural production,but there is a trend of heavy metal accumulation; and it is therefore necessary to perform regularly monitoring in the later stage to provide an sound environment for the high-quality agricultural production.