In order to improve TiO2 photocatalytic activity ZnFe2O4/TiO2 nanocomposites with different ZnFe2O4 mass loading were produced. Obtained ZnFe2O4 nanoparticles were coupled with TiO2 via microwave-assisted hydrothermal method in order to improve photon absorption in a range of visible light. Prepared nanostructures were characterized with scanning electron microscopy and X-ray diffraction. Photocatalytic activity of prepared samples was investigated by degradation of methylene blue under different light sources – LED, Hg and Osram Vitalux lamps. ZnFe2O4 consisted of spherical nanoparticles with average size of 15 nm. TiO2 spherical nanoparticles size was in a range of 30÷45 nm. The results shown that doping TiO2 with ZnFe2O4 nanoparticles increased photocatalytic activity. Photocatalytic activity increases as mass loading of ZnFe2O4 decreased.