Biofiltration is a cost effective air pollution control technology for volatile organic compounds. Biofiltration of ethanol vapour from air stream was evaluated in this study. Experimental investigations were conducted on a laboratory scale biofilter, containing mixture of compost and polystyrene inert particles as the filter materials. Mixed consortium of activated sludge was used as a inoculum. The continuous performance of biofilter for ethanol removal was monitored for different concentrations and flow rates. The removal efficiencies decreased at higher concentrations and higher gas flow rates. A maximum elimination capacity of 195 g m-3 h-1 was achieved. The response of biofilter to shut down and restart-up operation showed that the biofilm has got a good stability.