The cleavage of cumene hydroperoxide in the presence of H-form USY zeolites to form phenol and acetone has been examined. For comparison, the same reaction, catalyzed by Y-, ZSM-5, beta-zeolites, as well as sulfuric and heteropolyacids is performed. As appeared, HUSY zeolites of high Si/Al ratio (15 and 40) are sufficiently active catalysts, and their efficiency is comparable to that of sulfuric acid. Such outstanding catalytic performance of HUSY should be attributed to combination of favourable porous topology, sorption properties and relatively strong acidity of the internal surface. The acid strength of HY and HUSY zeolites is roughly estimated in terms of H/D exchange between deuterated acetone and water over the solid acid, while their sorption properties are estimated based on H2O-TPD measurements. (c) 2007 Elsevier B.V. All rights reserved.