Mesoporous titania (TiO2) was synthesized by hydrothermal method using cetyltrimethyl ammonium bromide (CTAB) as a template and using anhydrous ethanol and tetra-n-butyl titanate (TBOT) as raw materials. Mesoporous titania solid superacid and nanosized titania solid superacid catalysts were prepared by wet impregnation method. The structure and property of as-prepared samples were characterized by means of XRD, FT-IR and N-2 physical adsorption. The esterification of salicylic acid with isoamyl alcohol and the condensation of cyclohexanone with ethylene were used as model reactions to test the catalytic activities of the catalysts. On the other hand, the comparison of catalytic activities of the prepared solid superacid catalysts and the conventional liquid acid H2SO4 was also carried out under the same experimental conditions. The results show that the catalytic activities of the prepared solid superacid catalysts were higher than that of the conventional liquid acid H2SO4, and that the catalytic activity of mesoporous TiO2 solid superacid is the highest among the three catalysts. Mesoporous TiO2 solid superacid is a good catalyst for the synthesis of isoamyl salicylate or cyclohexanone ethylene ketal. (c) 2008 Elsevier B.V. All rights reserved.