In this work, magnetic and optical properties of magnetic nanoparticles were investigated, where the particles of iron oxide were prepared with a co-precipitation route and the component of gold was built up by reduction of AuCl4- on the surface of iron oxide to assemble nanocomposite structures in the form of an electrostatic stabilized suspension. The size of the particles obtained with TEM increased from of 8.9 ± 2.7 to 16 ± 6 nm after the procedure of hybridisation. In order to distinguish the impact of the gold on the optical properties, UV-Vis and Raman spectroscopy techniques were used. Magnetic properties were studied in the temperature range of 5-300 K and the superparamagnetic state of MNPs at room temperature was confirmed for both systems.