Biological treatment using attached growth on a rotating biological contactor (RBC) was used for the wastewater from Palm Oil Mill industries, which contains high strength of organic compounds, COD of about 16,000 mg/l. An acclimated Saccharomyces cerevisiae with POME was used as the initial biomass for the attached growth on bio-discs. After 5 days, 91% BOD removal was achieved in a batch experiment. Eighty-eight percent removal of COD was obtained with 55 h HRT. High surface COD loading of 38-210 g COD/m(2) day was implemented. Eighty percent TKN and 89% SS removal were obtained in the bench scale RBC. The maximum specific growth rate and the reaction rate were 0.82 day(-1) and 0.3 m(3)/m(2) day, respectively. The high organic loading of POME has been treated successfully in a bench scale RBC. (c) 2005 Elsevier Ltd. All rights reserved.