By using the industrial waste boron mud as raw material, graphite as reductant, coke particles as burying materials. During carbothermal reduction process, the Mg-Fe forsterite phase in boron mud row materials can transformed into forsterite and Fe2O3 at 1550°C and 1600°C for 3 h, and the Fe3C can be generated from the partial reduction of Fe2O3 with graphite, The main phase in samples calcined under 1650°C for 3 h contained forsterite, Fe2O3, Fe3C and β-SiC. The compound powder of Mg2SiO4 and β-SiC was prepared through the carbothermal reduction process. The effects of different graphite proportion (theoretical proportion, exceeding 10%, 50% and 100%) and firing temperature (1550°C, 1600°C and 1650°C) on the phase transformation and microstructure of the products were investigated by XRD, SEM and EDS. The results show that β-SiC powders were obtained at 1650°C for 3 h when graphite content was theoretical.