Abstract: Tributyl phosphate (TBP) is a typical kind of radioactive organic waste, proper treatment of which is very important to the sustainable development of nuclear industry. A batch type equipment of supercritical water oxiadation (SCWO) was established to explore the oxygenolysis of TBP. The results show that the degradation products of TBP do not contain hazardous matters, with CO₂ in gas phase while CO^2-₃, PO^3-₄ and unreacted organics in liquid phase, confirming the feasibility of processing TBP by SCWO technology. The effects of reaction temperature, pressure, and other factors on the decomposition ratio of organics were studied and the optimal reaction condition was determined as 450 ℃, 24 MPa, TBP initial concentration of 0.05 mol/L and H₂O₂ of one time excess rate. Under such condition, while the residence time is 10 min, the decomposition ratio of organics reaches 99.9%.