Background : Disinfection is essential for the prevention of hospital infection. Medilox, an super oxidized water generated by Medilox (SOO SAN EC CO., LTD. Yongin, Korea) was developed as a disinfectant in Korea. This is not costly and does not caany clinical problems and environmental pollution. We evaluated bactericidal activity ofMedilox against several clinical isolates and standard strains. Method : Clinical isolates and reference ATCC strains were exposed to Medilox, an super oxidized water (80 ppm ofHOCl) generated by Medilox (SOO SAN ECCO., LTD. Yongin, Korea) for the various periods (0.5, 1, 2, 5, and 10 minutes). After the exposure mixture of microorganisms and Medilox solution was inoculated into tryptic soy broth and onto tryptic soy agar, Sabouraud dextrose agar or Ogawa medium and cultured at 35C. Results: All strains of bacteria, yeasts, mycobacteria and vegetative form of Bacillus subtilis were killed within 30 seconds after an exposure to Medilox (80 ppm ofHOCl) under clean and dirty conditions. But, spore form of Bacillus subtilis was killed within 5 minutes. Conclusion: It may be recommended that Medilox can be used for the effective disinfectant for hospital environments and high-level disinfectant for hospital infection control.