The fumed silica produced by Xinjiang Jingshuo Company comprehensively utilizes by-products in the polycrystalline silicon industrial process-silicon tetrachloride and hydrogen as raw materials to produce fumed silica. After the preheated material undergoes a high-temperature hydrolysis reaction, a gas-solid mixture containing a large amount of silica is obtained. After cooling, aggregation, separation, deacidification and packaging, a high-quality silica product is obtained with a purity of more than 99.9%.