In this investigation nanostructured ferrite filler reinforced polymer composites are investigated. Nanostructured ferrite fillers were obtained by means of plasma treatment and sol-gel combustion synthesis. Simultaneously commercial nanostructured nanofiller were used as a reference. Most important technological parameters for the synthesis of the nanostructured ferrite fillers by both previously mentioned methods were defined. Certain physical and structural characteristics of the manufactured ferrite nanopowders were determined. Different techniques of melt blending were used in order to optimize dispersion of the nanostructured ferrite filler in a polymer matrix. Several mechanical, thermal and magnetic characteristics of the manufactured nanocomposites were investigated.