Selenium is an essential trace element in human body and has important biological functions.In this study, the contents of selenium in soil, atmospheric dry and wet deposition, irrigation water, fertilizer, rock and staple crops (rice, wheat, soybean, rape and corn) in the northeast of Shayang County of the Jianghan plain were determined.Through the spatial and vertical distribution characteristics of soil selenium, by integrating factor analysis, cluster analysis, correlation analysis and contribution statistics of related factors, the source of selenium in the rich soil is discussed, and the degree of bioenrichment of soil selenium is analyzed. The results showed that the background value of selenium in the surface soil of the study area is 0.25 mg/kg, which is slightly lower than the background value in the Jianghan River basin and the background value of soil (A layer) in China. The result of R-type factor analysis shows that factor F1 reflects the characteristics of the original soil background, factor F2 reflects the basic characteristics of soil parent material, factors F3 and F4 reflect the influence of human activities on the distribution characteristics of soil elements. The spatial distribution characteristics of selenium and soil element combination characteristics in the surface soil show that the surface soil selenium has strong spatial autocorrelation and is greatly influenced by natural soil parent material. The high value of selenium is mainly distributed in the alluvial zone of the Han River. The vertical profile of typical soil revealed that there was some exogenous input in the soil high selenium area in the Han River alluvial zone. The surface soil in the study area was obviously affected by human activities, but the contribution of atmospheric dry and wet deposition, irrigation water and fertilizer were low. The selenium enrichment degree in the edible parts of crops is as follows: soybean>wheat>rice>rape>corn, and some soybeans showed selenium super enrichment. The distribution area of selenium-rich crops was consistent with that of selenium-rich land, which had the potential of sustainable development and utilization.