To obtain an alkylcatechol with an excellent hydrogen peroxide selectivity and alkylphenol selectivity, and remarkably improved in productivity by reacting an alkylphenol with hydrogen peroxide under specific conditions.

This method for producing an alkylcatechol comprises reacting (A) an alkylphenol with (B) hydrogen peroxide in the presence of (C) perchloric acid, (D) a phosphorus atom-containing oxygen acid and its metal salt, and (E) a ketonic organic solvent. The components A, C and D are used in amounts of 3-30, 0.05-10 and 0.05-10 mol.%, respectively, on the basis of the component B. The method, in detail, preferably comprises introducing and mixing the component A, the component E, the acid metal salt and the component D, or the component C and the component D, and subsequently introducing and reacting the component B in the reaction system in a temperature condition of 80-150°C under stirring.