Removal of pentachlorophenol from water is investigated using the surfactant-enhanced cross-flow membrane filtration technique in which anionic surfactant; sodium dodecyl sulfate (SDS) is the carrier of pentachlorophenol. The separation performances are studied by varying SDS concentrations (<< critical micelle concentration, CMC). The association between pentachlorophenol and SDS leads to increase their effective size of the feed solutes and thus results the improvement in separation performances of the membrane. The performance is co-related with the separation of markers (glucose and sucrose) as well as salt rejection of the membrane. SDS, in feed induces the charge due to its polar head and thus separation improves due to electrostatic repulsion of membrane and associated molecule. The higher hydrophobicity of pentachlorophenol is also the factor. The study reveals that there is better improvement in pentachlorophenol separation upon addition of SDS for the thin film composite membrane which is of more permeability. (C) 2007 Elsevier B.V. All rights reserved.