Abstract: Aim To study the degradation of TNT in water by ozone ultraviolet advanced oxidation process (O 3+UV). Methods The concentration changes of various compounds such as TNT, trinitroaromatic compounds, O 3, etc. were investigated by experiments. Results and Conclusion TNT can be degraded more faster by combining O 3 with UV radiation while very slowly by only using O 3. A high pH does not improve the removal efficiency of O 3+UV process significantly. There still exist some trinitroaromatic compounds in the solution after TNT being processed, and they will reduce slowly after the mass fraction is less than 25%. The O 3+UV process is not suitable for the final treatment of trinitroaromatic compounds.