Destruction of 1,1,2-trichlorotrifluoroethane (CFC113) in supercritical and subcritical water was performed over a wide range of pressure at 673 K. The hydrolysis reaction of CFC113 in the supercritical water could lead to complete destruction of CFC113, while the CFC113 dest- ruction below the critical pressure of water was quite low. The Cl^- destruction yields were higher than those of F^- over the whole pressure range including both supercritical and subcritical regions, which implies that the bonding energy of F^- on the backbone of CFC113 is stronger than that of Cl^-. The destruction yields represented by two ions were found to have the linear dependency on the reduced water density.