To investigate the performance of a compost biofilter treating toluene vapor during intermittent loading, a biofiltration system was set up. This system was inoculated with a special type of white-rot fungus, Phanerochaete chtysosporium. The system was loaded 10 h per day on 0.096, 0.024, 0.06 m(3)/h of air flow rates, and 173.1 and 52.6 mg m(-3) of pollutant concentration while there was no aeration to the system during the remaining 14 h of the day. Maximum removal efficiency and elimination capacity obtained were about 92% and 1913.7 mg m(-3) h(-1), respectively. The fungal biofilter showed its robustness to the alterations in inlet toluene concentration and gas flow rate. The kinetic of biological reaction was studied by application of Monod type equation. The kinetic constants K-m and r(m) are evaluated as 3.495 g m(-3) and 50 g m(-3) h(-1), respectively. The results confirmed that the fungal system could effectively remove toluene in such a harsh condition without adding excess nutrient solution and during intermittent loading. (C) 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.