Supercritical water oxidation characteristics of aqueous phenol solution(500 ppm) was experimentally evaluated using a stainless steel 316 tubular-type reactor(0.21 cm ID x 34 cm L). The orders of reactions and rate constants with respect to the concentration of phenol, oxygen and water were determined under various oxidation conditions(i.e., temperatures : 300-440℃, pressures : 180-290 bar, percent of excess amount of oxygen : 0, 300, 600, 800 %, mean residence time : 0.7-11 sec). The conversion of phenol was linearly proportional to the residence time. For example, more than 90 % of phenol was oxidized at the residence time of 5 sec. Within the experimental conditions, the orders of oxidation with respect to phenol and oxygen concentrations were 1 and 0.437±0.027, respectively. Reaction order of water was proportional to density at constant temperature and pressure, and it was 0.653±0.027. The activation energy for the oxidation reaction at 240 bar and 300-440℃ was 18.31 kcal/mol.