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We have successfully synthesized core/shell type SrTiO3/Fe3.O4, SrTiO3/ -Fe2O3 and SrTiO3/ -Fe2O3 nanoparticles by using an ultrasound enhanced ferrite plating method and subsequent heat treatments in air. Scanning electron microscope and X-ray diffraction measurements have revealed that the Fe3.O4, -Fe2O3 and -Fe2O3 (20 nm thickness) are uniformly plated on SrTiO3 (80 nm in diameter), i.e., forming electric/magnetic-oxide core/shell nanoparticles. The magnetic properties of the core/shell nanoparticles are found to be similar to corresponding bulk ferrite materials. However, both SrTiO3/Fe3.O4 and SrTiO3/ -Fe2O3 show rounded hysteresis curves, which might be due to the formation of magnetic domains. The optical absorption spectra of the nanoparticles in the low-energy region can be explained by using the dominant optical transitions of Fe ions in the octahedra sites along with possible effects of the nano-size and the core/shell form.