A process for producing a polyhydroperoxy aromatic compound by oxidation of an aromatic hydrocarbon, e.g., 4,4'-diisopropylbiphenyl and 4,4'-diisopropylnaphthalene, with molecular oxygen is disclosed, in which the oxidation is carried out in the presence of a metal ion selected from cobalt, nickel, zinc and lead ions. Even in using a reaction apparatus made of an iron-containing metal generally employed in industry, a high conversion of secondary alkyl groups can be reached, and the desired polyhydroperoxy aromatic compound can be obtained in a high yield.