Oxidation of chemical warfare agents (CWAs) such as Sulfur Oxidation of chemical warfare agents (CWAs) such as Sulfur Mustard (HD) and Soman (GD) and their simulants 2-chloroethyl ethyl sulfide (2-CEES) and dimethyl methylphosphonate (DMMP) in supercritical water were studied by a batch reactor. Results showed that HD, GD and their simulants 2-CEES and DMMP could be effectively destroyed into their corresponding mineral compounds by supercritical water oxidation (SCWO). The mineral ratio was a function of reaction temperature, reaction time and oxidant concentration. But reaction temperature seemed to have more important effect on the mineral ratio than other two factors. Sulfur compounds 2-CEES and HD could easily be mineralized under 475°C and the inorganic products were mainly SO32- and SO42- , while complete oxidation of organic phosphorus reactants GD and DMMP needed a high temperature of >600°C. And under relatively low temperature, DMMP tended to form a white organic phosphorus polymer with P-C and P-O-P bonds. Results also indicated that P-F bond was more easily broken than P-C bond.