Abstract: Li2SiO3 powders were prepared at low temperature via hydrothermal process using LiOH·H2O and TEOS as raw materials. The effects of the reaction time, temperature and pH value on the preparation of Li2SiO3 powders were investigated systematically. The morphology and thermal stability of Li2SiO3 powders were characterized by means of XRD, SEM and FTIR. The results showed that pure Li2SiO3 powders were obtained via hydrothermal treatment at 100 ℃ for 72 h. This powders showed very good thermal stability that no decomposing reaction or phase change would happen even after calcined at 1 100 ℃. The nano Li2SiO3 powders (100~200 nm) were obtained at 100 ℃ as observed by SEM.