Sulfated zirconia has been studied widely in recent years, particularly for its potential applications as solid catalysts in acid-catalyzed reactions. In addition, it has oxidizing properties that may play a role in synthesizing organic compounds. This paper introduces a series of SO42−/ZrO2 catalysts precipitated at different sulfuric acid concentrations (1–3 N) using a sol-gel method. The prepared catalysts were calcined at 300°C, 400°C and 500°C . In particular, surface acidity was measured using the n-butylamine method and by pyridine adsorption. A sulfated zirconia tetragonal phase was prepared in an acidic medium 1N H2SO4. An amorphous to crystalline phase transformation occurred when the calcination temperature was increased. The incorporation of SO42− in ZrO2 increased the surface acidity of the catalysts. Moreover, acidity increased with increasing calcination temperature from 300°C to 500°C and then decreased. Hydrous zirconia was precipitated in an acidic medium followed by calcination to produce solid materials with useful properties that favor their application in photocatalysis by studying degradation of MB and MO dyes in water.