The search for inexpensive, high volume, easily accessible and environmentally friendly efficient remediation agents is one of the important tasks in the remediation of Cr(VI)-contaminated soil at this stage. Based on indoor simulated incubation experiments, the effects of tangerine peel addition and the initial concentration of Cr(VI) in soil on the removal process of Cr(VI) were studied, and the mechanism of tangerine peel remediation of Cr(VI)-contaminated soil was initially explored by Illumina NovaSeq high-throughput sequencing technology and X-ray near edge absorption spectroscopy (XANES). When the initial concentration of Cr(VI) in soil was (1600.13±298.11) mg/kg, the Cr(VI)-leaching concentration of Cr(VI) was (143.20±13.5) mg/L, and the amount of tangerine peel was added at 5% for 30 d, the concentration of Cr(VI) and its leaching concentration in soil decreased to (10.07±2.98) mg/kg and (1.02±0.30) mg/L, and the removal rates reached 99.37% and 99.29%, respectively. The results showed that the removal efficiency of Cr(VI) in soil increased with the increase of tangerine peel addition and decreased with the increase of the initial concentration of Cr(VI), the Cr(VI) in soil was converted to the Cr(III) after the addition of tangerine peel. In addition, tangerine peel affected the structure of bacterial community and its composition in Cr(VI)-contaminated soils. Addition of tangerine peel reduced the α-diversity and changed the β-diversity of bacterial communities. In the soil after the addition of tangerine peel, Actinobacteria was the optimal phylum, and four Cr(VI)-reducing bacteria, Microbacterium
, were enriched. The study showed that tangerine peel could effectively reduce the concentration of Cr(VI) and its leaching concentration in contaminated soil in a relatively short period of time. Its removal mechanism may be: (i) direct reduction of Cr(VI) to Cr(III) through small molecule organic matter hydrolyzed in the soil; (ii) indirect reduction of Cr(VI) toxicity by driving the enrichment of Cr(VI)-reducing bacteria as a carbon source.