Abstract: 【Objective】 To improve the effectiveness of organic selenium in selenium-enriched soil. 【Method】Field experiment was conducted to study the effects of different organic materials (biological humic acid, source humic acid and chicken manure) on the transformation of selenium in soil and the selenium absorption of wheat.【Result】The results showed that both biological humic acid and source humic significantly decreased soil pH. With the prolongation of application time, soluble selenium and exchangeable selenium in chicken manure and source humic acid-treated soil increased significantly compared with the control. The biochemical humic acid treatment significantly increased exchangeable selenium content, but there was no significant difference in soil soluble selenium content. Application of chicken manure and source humic acid significantly increased the selenium enrichment coefficient of wheat grain, while biochemical humic acid mainly increased the root enrichment coefficient. The selenium content of chicken manure and the source humic acid wheat grain was increased by 34.48% and 27.59% respectively compared with the control. 【Conclusion】Application of chicken manure and source humic acid could increase soluble selenium and exchangeable selenium content in calcareous and selenium-rich soils, thus increasing selenium content in wheat grains.