FIELD: catalyst conversion of hydrocarbons used for reforming of gasolines and preparation of aromatic compounds. SUBSTANCE: stock being processed comprising paraffin, naphthene and aromatic hydrocarbons having from 5 to 12 carbon atoms is made to contact with catalyst which contains matrix composed of gamma modification of aluminium oxide or mixture of gamma-and eta-modifications of aluminium oxide and at least one alloying metal selected from alkali and alkaline-earth metals, at least one halogen selected from group consisting of fluorine, chlorine, bromine and iodine, at least one noble metal selected from group composed of platinum and at least one promoting metal selected from group consisting of tin, germanium, indium, gallium thallium, antimony, lead, rhenium, manganese, chromium, molybdenum and tungsten. Said catalyst is subjected to hydrothermal treatment at temperatures ranging from 300 to 1000 C in steam-containing gas atmosphere. EFFECT: improved selectivity with respect to desired aromatic product and reduced gas formation. 23 cl, 4 ex, 2 tbl
