Abstract: Chromium slag leachate is rich in Cr(Ⅵ), which is highly toxic and migratory, posing serious harm to the ecological environment. There are fewer studies involving multiple aquifers and aquitards contaminated with chromium, and the main controlling factors affecting chromium migration and transformation are not yet clear. In order to investigate the migration and transformation patterns of chromium in soil under such condition, a chromium contaminated site was taken as an example in this study, the spatial distribution of Cr in soil at different depths, the different forms and proportions of Cr in uncontaminated and contaminated soils, and the factors such as iron and aluminum content in soil affecting the migration and transformation of Cr were analyzed by sampling and testing soil samples, and the combination using of methods such as mathematical statistics, Kriging interpolation and factor analysis. The results shown that (1) Soil below ground surface 40 m was polluted by Cr with different degrees around the chromium slag heap, and the percentage of Cr(VI) mass fraction was higher in clay or silt caly than in sand layer. (2) The proportion of Cr in weak acidic state in soil at different depths was less than 10%, and the proportion of Cr in residual state ranged from 37% to 63% in uncontaminated soil, but it mainly existed in the form of reducible state in contaminated soil. The exchangeable and reducible states of Cr were the main forms of Cr migration and transformation at this site. (3) There was a linear relationship between the Fe and Al content in soil at different depths, and the increase of Fe and Al content could enhance the adsorption capacity of soil for Cr(Ⅵ), especially in the silty clay and clay layers. (4) Increased cation exchange capacity (CEC) promoted the adsorption of Cr(Ⅲ) in soil at different depths. Manganese oxides favored the conversion of Cr(Ⅲ) to Cr(VI) through adsorption, oxidation reaction and microbial action, while organic matter drived the conversion of Cr(VI) to Cr(Ⅲ) through adsorption, reduction reaction and microbial action. Soil pH affected the adsorption of Cr(Ⅲ) and Cr(VI) by changing the surface charge of particle, and also promoted the adsorption of Cr(Ⅲ) together with CEC, or affected the adsorption of Cr(VI) with organic matter. Therefore, accurate identification of site hydrogeological condition is essential for analyzing the transformation of Cr in soil. The results of this research can provide strong support for risk management and post remediation of chromium slag contaminated sites.