A sensitivity analysis of a model that describes the biooxidation of Total Reduced Compounds (TRS) using a biotrickling filter is presented. Consistent results are obtained using three methodologies; Standard Regresion Coefficients (SRC), Variance-based sensitivity index (VSI) and the method of Morris. The model presents a highly linear behavior of the uncertain parameters. It is shown that the properties of the biofilm and the parameters related with the kinetics have the highest influence on the behavior of the model, on the other hand the properties related with mass transfer have a low influence.