The alkylation of phenol with cyclohexanol and cyclohexene in the presence of HY and dealuminated/ultrastable Y zeolite catalysts was studied over a range of temperature 140-220 degreesC at atmospheric pressure for reaction times of 2-12 h. The molar ratio of the reactants (cyclohexanol:phenol) was varied from 1:1 to 1:5. A mixture of isomeric cyclohexylphenol was obtained consisting mainly of 4-cyclohexylphenol. The 2-/4-product ratio decreased with increasing temperature, molar ratio of reactants and increased contact time. The reaction temperature also plays an important role. At lower temperatures, ortho product predominates, but at higher temperatures para isomer predominates. HY samples dealuminated at medium temperatures (500-700 degreesC) also increases the para-selectivity.