Understanding the spatial distribution and influencing factors of selenium (Se) content in cultivated soil in Yizhang County is of great significance for the development of characteristic Se-rich agricultural products and the protection of human health. The distribution characteristics and influencing factors of Se content in cultivated soil in Yizhang County were analyzed by field investigation, laboratory analysis, mathematical statistics and model simulation. The results showed that: 1)The average Se content of topsoil in Yizhang County is 0.64 mg/kg, ranging from 0.13 to 2.80 mg/kg, and the coefficient of variation is 44.57%, which is a moderate degree of variation. 2)There is a middle-high selenium-rich belt from Yuxi Town to Meitian Town, Jiangshui Town, Changcun Township, Yiliu Town, Fence Town and Tiantang Township from northeast to south in the middle. The nugget effect value is 0.505, indicating that the spatial autocorrelation degree of soil Se in Yizhang County is moderate, and soil Se content is affected by spatial structure factors (natural factors) and random factors (human factors). 3)There are significant differences in Se content in soils developed from different soil parent materials. Soil Se content of cultivated land developed from slate shale is the highest, with an average selenium content of 0.76 mg/kg. 4)Different soil types have obvious effects on selenium content, and the average content of Se in fluvo-aquic soil and black calcareous soil is the highest, reaching 0.68 mg/kg, and the average selenium content of purple soil and yellow soil is only 0.54 mg/kg and 0.53 mg/kg, respectively. 5)Correlation analysis showed that soil Se content is significantly negatively correlated with pH and positively correlated with organic matter, Mn, Cu, Zn and CEC. In developing Se-rich agricultural products, the distribution characteristics of soil Se content should be considered, and the corresponding soil management, scientific fertilization and agronomic measures should be combined.