In this paper a mechanistic model was developed to predict the performance of a trickling biofilter as a function of temperature. Energy and mass balances were used to obtain the model equations. The expression for the bioreaction rate was modified in a way that it included the effect of temperature on the rate of bioreaction. The effects of temperature on Henry's law constant and diffusivity of the pollutant were also considered. The model equations were solved using finite volume method. The results in the literature from a bench scale trickling biofilter treating toluene were used to verify the model. The model predicted the experimental data reasonably well. Sensitivity analysis showed that the performance of a trickling biofilter is sensitive to the variations in maximum specific growth rate of microorganisms, and Henry's law constant of the pollutant as a result of variation in temperature. The model could also predict the water loss due to the evaporation of the liquid medium. (C) 2010 Elsevier B.V. All rights reserved.