The preparation and characterization of catalytic membranes containing La-based perovskites are reported. The membranes were prepared by in situ crystallization of different perovskites inside a porous alpha-alumina matrix. Preponderance of the Knudsen-diffusion regime during membrane operation was obtained with perovskite loads of 2 wt% and higher. The catalytic membranes obtained were used as combustors of VOCs (toluene and methyl ethyl ketone) contained in air streams, at concentrations between 875 and 3450 ppmV, and space velocities of up to 27200 h(-1). The membranes were operated in the flow-through mode, which resulted in total VOC combustion at moderate temperatures.