The interaction of oxygen with iron deposited on polycrystalline aluminum surfaces has been investigated using AES, XPS, and ARXPS. The growth of the iron on the aluminum surfaces occurs in two stages: formation of FeAl islands 10-ML thick up to a coverage of theta (FeAi) approximate to 0.65, followed by the formation of metallic iron islands 8-ML thick that grow over the intermetallic islands previously formed. For surfaces containing FeAl islands alone, the chemical information obtained by the analytical techniques shows that oxygen exposure causes the formation of aluminum intermediate oxidation states Al2+ and Al1+, in addition to Al3+, which are attributed to the formation of Al-O-Fe cross-linking bonds at the interface. The analysis of the Fe 2p peak shape shows that no iron oxide is formed, the small changes observed in this band being attributed to Fe atoms in an aluminum depleted layer at the interface. The oxidation of surfaces containing iron islands leads to results consistent with the formation of an Fe2O3 oxide film that grow over a film containing a mixture of intermediate aluminum and iron oxidation states.