A series of potent inhibitors of tyrosinase and their structure-activity relationships are described. N-Benzylbenzamide derivatives (1-21) with hydroxyl(s) were synthesized and tested for their tyrosinase inhibitory activity. With this series, compound 15 provided a potent tyrosinase inhibition: it effectively inhibited the oxidation of l-DOPA catalyzed by mushroom tyrosinase with an IC(50) of 2.2microM.