The composition of aromatic sulfur compounds of oils formed during the thermolysis (160-650A degrees C) of resins and asphaltenes from heavy crude of the Permian-Carboniferous deposit in the Usa oilfield (Komi Republic) has been studied. (C-1-C-4)-alkylbenzothiophenes; dibenzothiophene and (C-1-C-3)-alkyl derivatives; and phenanthro[4,5-bcd]-, benzo[b]naphtho-, triphenyleno[1,12-bcd]-, dinaphtho[2,3-b:2',3'-d]-, perylo[1,12-bcd]-, benzothieno[3,2-b]benzo-, benzo[1,2-b:3,4-b']bisbenzo-, and phenyldibenzothiophenes have been identified. The tri- and tetracyclic structures with predominance of dibenzothiophene and benzo[b]naphtho[2,1-d]thiophene prevail in the oils obtained by the thermolysis of resins and asphaltenes.