This study was performed to develop a method for removing polychlorinated biphenyls (PCBs) from soil using hydrogen peroxide under high pressure (0.5-2.5 MPa) and high temperature (150 degrees) in an aqueous phase (wet peroxide oxidation). The level of PCBs in highly contaminated soils could be reduced below environmental standards by performing this oxidation process repeatedly. The ability of this process to remove PCBs was almost the same among PCB homologue groups. Although removal of PCBs from black soil with high organic content (26%) was only 72.6%, removal from soils with lower organic content (4-16%) was more than 90%. These results indicated that the wet peroxide oxidation is effective for removal of PCBs from soil.