The study was aimed at developing a model simulating the photooxidative degradation of single-benzene ring typically water pollutants. In that purpose, 30 aromatics with different types, numbers and positions of substitutes were treated by UV/H2O2 process. The hypothesis of structural dependence of degradation kinetics was tested by combined mechanistic and structural-relationship modeling approach. The treatment is simulated by mechanistic model (MM) based on simplified degradation scheme. QSPR models were developed to predict the parameters of MM in dependence of parent pollutant structure. The applied combined approach yielded high accuracy in simulating the overall system behavior, accurately predicting the effectiveness of UV/H2O2 process by the means of parent pollutant conversion and mineralization of overall organic content, as well as describing the pH changes and consumption of oxidant during the treatment. (C) 2014 Elsevier B.V. All rights reserved.