Abstract: This is an essay in the field of ceramics and composites. To study the effect of water glass on the hydration reaction of cement and performances of cemented fine tailings backfilling materials (CTB), compressive strength test, X-ray diffraction (XRD), thermogravimetric (TG), scanning electron microscope (SEM) were used to investigate the effects of water glass dosage on the compressive strength of CTB, hydration products, and microstructure of cement pastes. The results showed that, for a given range, the addition of water glass consumed the Ca(OH)₂ in samples and generated large amounts of calcium silicate hydrate (C-S-H) gels, forming a compact microstructure, which was beneficial for the rapid development of strength. However, the further increase in the water glass dosage did not significantly improve the quantities of C-S-H gels because the Ca(OH)₂ in cement system was completely consumed, leading to a weak enhancement in the strength of CTB.