The object of the present invention is to provide a method for manufacturing cycloalkanol and/or cycloalkanone with favorable selectivity coefficient by oxidizing cycloalkane with favorable degree of conversion.In the present invention, cycloalkane is oxidized with oxygen in the presence of a catalyst such that cobalt is supported on layer silicate cycloalkane. Said oxidation is performed in the coexistence of a heteropoly acid compound and the heteropoly acid compound preferably contains cobalt as a central element and/or a skeletal element.