A mesoporous sulfated zirconia-silica material with high hydrothermal stability was prepared by a two-step hydrothermal treatment process in a pH range of 1.65-3. This material still showed high surface area, large pore volume, and uniform structure after steam treatment at 800 degrees C for 5 h. In cumene cracking, the material exhibited relatively steady catalytic activity even after steam treatment at 600 degrees C for 2 h.