Photocatalytic activity of TiO2 nanoparticles depends strongly on its crystallinity, specific surface area, morphology of the particles and used dopants. Promising is materials with high specific surface area and with modified composition. In the present work formation of active TiO2 nanoparticles in microwave synthesis and their modification with nitrogen and sulfur were studied. Anatase nanopowder and 10M KOH solution are used as raw materials. Microwave assisted synthesis method permits to obtain TiO2 nanofibres and nanowires with a diameter of 10 nm and a specific surface area in the range of 70- 150 m2 /g. In order to improve the photocatalytic activity of nanofibers under visible and UV light, the samples are modified by their treatment at 500 o C and 380 o C in nitrogen and hydrogen sulfide gas streams for different time intervals. Photocatalytic activity was determined by degradation of the methylene blue solution under UV and visible light irradiation. The obtained samples show higher photocatalytic activity with respect to pure TiO2 nanofibers. The doped TiO2 nanofibers are appropriate for degradation of harmful organic compounds as well as for hydrogen production by water splitting.