Abstract:he investigating results of preparing high Performance Si3N4 powder by carbon reduction and nitridation from SiO2 is reported in this paper.lt has been studied that the effeCt of the technological factors such as the nitriding temperature,the nitriding time and nitrogen flow,etC.on the colour,particle shape,Pareicle size, particle distribution and phase structure of the nitriding products. The forming conditions of the amorphism,SiO2 and SiC products are discussed.Results show that the nitriding technological factors influence obviously the performances of the nitriding products.High quality St3N. POwder with high a phase ratio,fine particle and homogeneous particle distribution can be prepared by the technological conditions of using the nitriding temperature 1450t,the nitriding time 2h and the nitrogen flow 2.5L/ min.