Abstract: Advanced oxidation processes, such as UV/H2O2, are methods able to remove diverse classes of organic contaminants and disinfect water and wastewater. However, the variation in the matrix composition can lead to the use of inadequate oxidant/radiation dose and disturb a correct treatment. The aim of this study was to model the UV/H2O2 disinfection process of secondary wastewater in presence of carbonate, nitrate, metals and emerging contaminants (EC) using as biological indicator the Escherichia coli. The ROH,UV/H2O2 was applied to quantify and compare the E. coli inactivation by the radical pathway. The metals Cu, Fe and Zn caused an improvement while carbonate and the emerging contaminants caused a decrease on ROH values for both stages of UV/H2O2. The modelling results based on ROH values demonstrate that E. coli inactivation can be predicted satisfactory (R2 > 0.96), being a useful tool for the generalized prediction of disinfection by UV/H2O2 Ver menos