Process for the catalytic hydrodealkylation alone of hydrocarbon compositions comprising C8-C13 alkylaromatic compounds mixed with C4-C10 aliphatic and cycloaliphatic products which, under the reaction conditions, undergo aromati-zation and subsequent hydrodealkylation, which comprises treating said hydrocarbon compositions in continuous and in the presence of hydrogen, with a catalyst consisting of a ZSM-5 zeolite, as such or in bound form, wherein the Si/Al molar ratio in the ZSM-5 ranges from 5 to 100, modified by means of the platinum-molybdenum couple, at a temperature ranging from 400 to 650° C., a pressure ranging from 2 to 4 MPa and H2/feedstock molar ratio ranging from 3 to 6. The presence of organic compounds containing heteroatoms such as sulphur, nitrogen or oxygen in the feedstock does not at all alter the performances of the catalyst according to the process object of the invention.