The adsorption of D2O and O2 on polycrystalline FeTiO3 (natural ilmenite) has been studied by x-ray photoelectron spectroscopy. Oxygen was found to absorb reactively with Fe0 on Ar+-sputtered surfaces at and above 150 K while D2O was found to adsorb molecularly or in ice layers below 170 K on both Ar+ and O+2 ion-bombarded ilmenite. The D2O desorbs at 170 K with either the formation of an OD complex or a strongly bound molecular layer of water.