The efficiency Of purification of air from volatile organic compounds (ethyl acetate) by means of bacteria (Pseudomonas fluorescens) immobilized on the TBR bed working at cocurrent flow of both liquid and gas phases has been tested in this work. The optimum technological parameters of the biodegradation process of the chosen pollutant have been determined and the kinetic equation parameters describing the rate of biological reaction have been estimated. The created experimental data base made it possible to verify the mathematical model of the process.