Abstract：The formation of adsorbable organic halogens （AOX） during treatment of Br--containing refractory wastewater， which was simulated by adding Br- to coking wastewater， by two advanced oxidation processes， UV/H2O2 and UV/PDS， was investigated under the optimized TOC removal conditions. The response surface method was used to optimize the reaction conditions achieving efficient removal of TOC， but when the Br- concentration increased from 50 mg·L-1 to 150 mg·L-1， the AOX concentrations in the UV/H2O2 and UV/PDS effluent increased from 0.56 mg·L-1 and 0.65 mg·L-1 to 1.44 mg·L-1 and 1.63 mg·L-1， respectively， which were much higher than the influent AOX concentration （0.08 mg·L-1）. The simulation results of the steady-state concentration of reactive halogenated species （RHS） showed that the RHS concentration in UV/PDS was generally higher than that in UV/H2O2， which was an important reason for the difference in AOX concentration between the two effluents. The results of the experiments on the separation and oxidation of organic matter in the wastewater showed that organic with molecular weights between 1000 Da and 10000 Da and hydrophobic bases （HOB） were easier to form AOX during the oxidation， and their AOX generation per unit TOC reached 0.24 mg AOX and 0.053 mg AOX （UV/H2O2） and 0.25 mg AOX and 0.069 mg AOX （UV/PDS） respectively at a Br- concentration of 150 mg·L-1. Brominated alkanes and brominated anilines were the major brominated organics identified in effluent， which are toxic and pose a potential threat to the receiving water bodies.