The developed innovativegreen electrolyzed catalysis (EC) system can generate high concentrations of hydroxyl radical (OH·)nanobubbles, which can remediate TPH-contaminated soilgroundwater effectivelyeconomically. The EC system applies high voltagehigh electric fielduses direct current to change the structure of water molecular. Under activities of high voltagecatalystselectrolysis reactions, the electric discharges can produce EC water containing ·OH for TPH oxidation without secondary pollution. Nanobubbles can produce ·OH continuously after bursting.