The dinitrotoluene (DNT) wastewater treatment was investigated in a semi-continuous supercritical water oxidation system with the temperatures from 425 ℃ to 570 ℃ and the resident time from 0 s to 60 s at 24 MPa and 300% excess oxygen. Results show that increasing temperature and resident time can increase the DNT and chemical oxygen demand (COD) removal efficiencies. Treatment for approximately 20 s at a pressure of 24 MPa, temperature of 550 ℃ and oxygen excess of 300%, results in destruction efficiencies of over 98.89% for DNT and 98.99％ for COD. The DNT and COD removal efficiencies are strongly dependent on temperature and resident time during 425-550 ℃ and 0-20 s. Under the treatment condition of 425-550 ℃, 24 MPa and 300% excess oxygen, the reaction order respect to DNT is 3.630, the activation energy is 24.19 kJ·mol^-1, and the Arrhenius pre-exponential factor is 7.109×10⁵ s^-1.