A process for producing an aromatic hydroxyl compound alkylated at the ortho position in high yield by subjecting an aromatic hydroxyl compound and an alkyl alcohol to a gas phase catalytic reaction in the presence of a metal oxide catalyst. The aromatic hydroxyl compound is a mixture of a phenol and ortho cresol, and the amount of ortho cresol in the mixture is 0.6 mole or less per 1 mole of phenol.