Mesoporous MSU-X alumina molecular sieves were synthesized through the neutral (NI0)-I-0 assembly pathway using aluminum sec-butoxide as the precursor and a triblock poly(ethyleneglycol)-poly(propylene glycol)-poly( ethylene glycol) as the structure-directing agent. Their surface acidity and basicity as well as textural properties were characterized by NH3-TPD; CO2-TPD, IR spectroscopy and N-2 adsorption methods. The materials are abundant in surface weak acid sites and weak-medium basic sites. They are more active than the commercial gamma-Al2O3 catalyst for the CS2 hydrolysis reaction, and the temperature of 90% conversion of CS2 on the mesoporous alumina is 130 K lower than that of gamma-Al2O3.