In the present study the effects of addition of iron on the catalytic activity and Si tolerability of Pt/gamma-Al2O3 in the total oxidation of volatile organic compounds were investigated. Preliminary results showed that: there is a noticeable improvement effect on Si-tolerance of catalyst, particularly for short term poison exposure. Bulk analysis of deposited silicon on the catalyst surface indicated that both Pt/gamma-Al2O3 and iron-doped pellets had roughly the same silicone uptakes. Deactivation of catalyst was reversible and much faster for iron doped sample. The promoting effects of iron were related to its electronegativity and, to blocking of fewer Pt sites when iron is present at the surface of the catalyst.