The present study investigates the removal of TOC and atrazine from surface water and ultrafiltration permeate with various oxidant mass flow ratios of ozone-hydrogen peroxide at pH 7. Ultrafiltration (UF) was used as a pre-treatment to assess the influence of feed water quality on the advanced oxidation processes (AOP). It was observed under comparable conditions that the removal efficiency of Total Organic Carbon (TOC) in the UF permeate is comparable to that in surface water. The application of ozone/hydrogen peroxide mixtures has a pronounced effect under our experimental conditions on both the TOC removal efficiency and the atrazine removal rate. Finally, it was concluded that the use of ultrafiltration as pretreatment for oxidation processes has no significant positive effect on both the removal of atrazine and TOC. (C) 2010 Elsevier B.V. All rights reserved.