In-situ chemical oxidation remediation can realize the dosing， mixing and reaction of chemicals to contaminated soil and groundwater through shallow mixing， injection well technology， direct push injection， high pressure rotary jet grouting and deep mixing. In view of the hydrogeology， pollution distribution and remediation target of the organic contaminated site， the deep mixing method was used to design and implement the in-situ chemical oxidation remediation， and the detected concentration of each target contaminant in the soil after remediation is significantly lower than the initial concentration in the site investigation and lower than the target for remediation. The engineering practice shows that the deep mixing method is applicable to the in-situ chemical oxidation remediation of organic contaminated sites with deep pollution depth and light pollution degree， and has the advantages of mature process， uniform mixing， less land occupation， small environmental impact， high cost performance and good remediation effect， and has broad application prospects. When the deep mixing method is applied in the field of site remediation， the corrosion of chemicals on equipment and pipelines， the safety protection of operators， and the bearing capacity of the site after remediation should be considered.