Iron oxide nanoparticles dispersed in aluminum (Al) or silicon (Si) oxides were prepared via a polymeric precursor derived from the Pechini method. The samples were characterized by thermogravimetric analysis, Fourier-transform infrared spectroscopy, X-ray diffraction, N-2 adsorption/desorption isotherms (Brunauer-Emmett-Teller, BET), Mossbauer spectroscopy, and vibrating sample magnetometry (VSM). BET analysis shows that the samples are mesoporous materials and have a high surface area. The size of the Fe2O3 nanoparticles in Al2O3 is smaller than that in SiO2. Mossbauer spectra of the samples show that the Fe2O3 nanoparticles in Al2O3 are non-magnetic at room temperature but magnetic below 50 K. The FeSi samples are magnetic at both room and low temperatures. The magnetic measurements with VSM confirmed this point.