In this paper, Se and the contents of As, Hg, Cr, Cd, Pb in the selenium-rich soils in the northern part of Ziyang County, Shaanxi Province are measured according to rock parent material soil structure, and the migration and accumulation characteristics of each element and the land risk are evaluated.The results show that the content of As, Hg, Cd and Pb in soil is increase (As 12.570 mg/kg, Hg 0.068 mg/kg, Cd 1.162 mg/kg, Pb 24.754 mg/kg), while the content of Cr and Se is decrease to 89.510 mg/kg and 1.445 mg/kg.Cd, As, Se and Hg are obviously enriched from rock to parent material, and the migration and accumulation coefficients are 7.612, 3.900, 3.854 and 3.175, respectively.Cd, Se and As from parent material to soil are also enriched, with migration and accumulation coefficients of 4.070, 2.644 and 2.502, respectively.The weathering leaching coefficient of Cr and Pb is as high as 41.847 and 7.983, indicating that the two elements are easy to be lost and enriched under the action of water leakage.The Krigin interpolation spatial distribution characteristics of the six elements are consistent with the strata and structures.It is found that the heavy metal accumulation in the high selenium geological background area is largely controlled by regional geological factors.The selenium-rich soil in the working area is closely related to the black carbon-bearing rock series of Cambrian-Ordovician-Silurian, which is the main source of soil selenium.In this paper, five grades of land risk assessment zones are divided according to the selenium enrichment degree, harmful elements pollution degree, organic matter content and other factors, providing technical support for the development of local selenium-rich characteristic agriculture.