Abstract: Abstract: With central south Hebei plain as the study area, to study iodine geochemistry of soil in detail and explored its controlling factors, the authors studied the distribution of iodine based on the analysis of iodine content in different soile stypes and different sedimentary environment.The results show that the most content of iodine element in different soile stypes of central south Hebei plain is coastal solonchak and bog soil.The sedimentary environment with more iodine element content in the deep soil is the lakes and swamps phase of Baiyangdian and coastal plain of Cangzhou,the sedimentary environment with lower iodine element content is alluvial fan plain of Hutuo River in the middle of Taihang Mountain and Zang River. The distribution of iodine element in soil is significantly affected by physical factors and human factors in the area,with the physical factors play the leading role, on this basis, human factors have a greater impact on the iodine element content of topsoil.