Thin films containing TiO2/HZSM-5 are found to be more active for the photocatalytic degradation of phenolic wastewaters than films without zeolite. The optimum ratio of TiO2/HZSM-5 is found to be 1/4. The presence of zeolite increases the concentration of substrate near the photocatalyst and protects the organic support against the photodegradation. (C) 2003 Elsevier B.V. All rights reserved.