A process for activating a hydroalkylation catalyst in a first state comprising an acid component and a hydrogenating metal component, including: (i) treatment at a temperature of at least 120° C. in the presence of hydrogen for a first duration to produce a catalyst in a second state having a first hydroalkylation activity; (ii) contacting the catalyst in the second state with an aromatic compound and hydrogen under a hydroalkylation condition effective to convert at least part of the aromatic compound to a cycloalkylaromatic compound and produce a catalyst in a third state; and (iii) treating the catalyst in the third state at a temperature of at least 160° C. in the presence of hydrogen but advantageously in the substantial absence of the aromatic compound for a third duration to produce an activated catalyst in a fourth state having a third hydroalkylation activity greater than the first hydroalkylation activity.