Ti and V-contg. MCM-41 type mezoporous mol. sieves were prepd. and characterized by XRD, ICP and sorption measurements. The sieves were used as catalysts for liq. phase oxidn. of thiophene derivatives with Me(3)COOH under atm. pressure to the resp. sulfones. Conversion of the S compds. increased up to 100% with increasing reaction time (up to 3 h), temp. (up to 100 degrees C) and O/S ratio (up to 7 mol/mol).