The solid cultivation of Myceliophthora thermophila l-1D3b was compared in terms of endoglucanase enzyme activity in a horizontal drum for two methods of airflow: introduction of air above the bed (axial air flow) and introduction of air through an inner localized amid the bed equally perforated along its length (radial air flow). The mean enzyme activities were equivalent in both cases, being 92.3 and 92.4 U/g-ds, respectively. However, the fungal growth was not homogeneous along the axial position in the second situation and this was confirmed through the enzyme activities, indicating that the radial air flow along the axial position not has been uniform; while the fungal growth was uniform for the situation in which the air flow was preferentially axial. The results indicate that the configuration with radial air flow needs adjustments in the inner tube for an efficient and homogeneous aeration of the fermentative system.