Anaerobic digestion model no. I model of international water association was applied to a full scale anaerobic co-digestion process for the treatment of the organic fraction of municipal solid wastes along with activated Sludge wastes originating from a municipal wastewater treatment plant. This operation was carried Out in a digester of 2000 m(3) in volume. It is operates at an average hydraulic retention time of 26.9 days with an average organic loading rate of 1.01 kg TVS/m(3) day, at a temperature of 37 degrees C with an average gas production rate of 0.296 m(3)/m(3) day. The aim of the present study is to compare the results obtained from the simulation with the experimental Values. The Simulated results showed a good fit for pH, methane and carbon dioxide percentages, biogas volume, chemical oxygen demand, total volatile fatty acids, inorganic nitrogen and inorganic carbon. (C) 2008 Published by Elsevier Ltd.