The volumetric expansion of silicon anodes in lithium-ion batteries leads to a shortened cycling life and rapid capacity decay. Consequently, it is imperative to enhance the cyclic stability of silicon anode materials. In this study, we employed a molten salt-assisted magnesiothermic reduction method and successfully devised a silicon nanomaterial reinforced with silicon carbide ( SF-Si) by utilizing silica fume containing elemental carbon, which is an industrial solid waste. The resulting SF-Si sample not only retained the SiC present in the silica fume but also converted the elemental carbon into SiC, achieving a SiC content of 16. 4% (mass fraction). Comparative analysis with silicon material prepared from heat-treated silica fume without elemental carbon removal (H-SF-Si) revealed that SF-Si exhibited superior cyclic and rate performance. It attained a high specific capacity of 2 584. 76 mAh·g - 1 in the first cycle, maintained an 83% capacity retention after 100 cycles, and even at a high current density of 5 A·g -1 , the average capacity remained at 877. 28 mAh·g -1 . These enhancements were primarily attributed to the higher SiC content. The study underscores the potential application of silica fume in the domain of silicon anodes for lithium-ion batteries, with its carbon element playing a constructive role in the preparation of silicon-based nanomaterials.