Abstract: In order to discuss the geochemical characteristics and influencing factors of selenium in cultivated soil of Pu′an County,Guizhou Province,based on the results of the geochemical survey and evaluation of 1∶50 000 farmland quality in the county,by means of parameter statistics,isoline drawing,correlation analysis and other methods,summarized the geochemical characteristics of selenium in the cultivated soil of this county,and research the influencing factors of selenium.The results show that the selenium rich cultivated land is rich in resources,and the distribution of selenium is mainly affected by the parent material.At the same time,the extensive distribution of rich organic matter and acid soil is also an important reason for selenium enrichment.