Silicon brick is an acid refractory with high load softening temperature and acid slag corrosion resistance, but it has poor alkali corrosion resistance. Therefore, it is of great significance to study the alkali corrosion resistance of different silica bricks for the application of silica refractories. Four kinds of silica bricks (JG-95# silica brick, BG-96A# silica brick, ZES-99# silica brick and DES-99# silica brick) were selected to compare and analyze the influences of the crystal phase composition and crystalline phase transition on the alkali corrosion resistance of four different silica bricks by chemical analysis, microscopic structure analysis, X-ray powder diffraction analysis and apparent porosity density analysis. The results show that the alkali corrosion resistance of ZES-99# silica brick and DES-99# silica brick is better than that of JG-95# silica brick and BG-96A# silica brick. Silica bricks with higher silica content have stronger alkali corrosion resistance, and silica refractories with cristobalite, tridymite and fused quartz as main crystal phases have good alkali corrosion resistance.