We have prepared iron doped TiO₂ samples by the impregnation of TiO₂ (Degussa—P25) with Fe(III) nitrate as an iron precursor. Obtained materials were then characterized by structural x-ray diffraction (XRD) and optical (Uv-vis, Raman) techniques. Later, we deposited very small gold nanoparticles (AuNPs; <5 nm) onto as-prepared supports by a colloidal deposition method, in which lysine was used as a capping agent and a short sonication time was applied to facilitate the dispersion and deposition of AuNPs. The presence of Fe⁺³ in the TiO₂ structure was confirmed by an increase in the number of oxygen defect sites that react with O₂ to form reactive oxygen species. Transmission electron microscopy (TEM) was used to determine the size of the gold particles before and after deposition. The AuNPs deposited on the FeTiO₂ exhibited good thermal stability against sintering, even at 500 °C for 4 h.