In this work, we have conducted a comparative study between the transport of electrons and positrons in aluminum and gold solid thin. films, in the examined primary energy range (0-4 keV), by using the Monte Carlo method. This comparative study has been used for three transport phenomena: transmission, absorption and backscattering and it will be useful for experimenters to choose between electron or positron beams for thin. film characterizations. Here, we have calculated quantities such as absorption probability, mean penetration depth, transmission probability, transmission energy distributions and backscattering coefficient, for both electron and positron. The agreement between our results and the available experimental data is found to be good within the limits of the statistical accuracy. (C) 2009 Elsevier B. V. All rights reserved.