Nanosized silicon nitride has been prepared reacting tetraethyl-orthosilicate, n-decanol and ammonium nitrate at temperatures between 800 and 10000C under argon atmosphere. An innovative technique has been used for the synthesis of silicon nitride by in-situ generation of nitrogen through a solgel route. The structure and phase composition have been characterized by infrared spectroscopy, transmission electron microscopy and X-ray diffraction. The average particle size of Si3N4 was in the range 6-12nmunder various reaction conditions. The probable reaction mechanism of Si3N4 formation is also deduced.