In this report, we describe the ability of ellagic acid (EA), a phenolic compound present in a number of fruits and nuts, to inhibit N-nitrosobenzylmethylamine (NBMA) tumorigenesis in the rat esophagus. When administered in a semi-purified diet at concentrations of 0.4 and 4 g/kg, EA produced a significant (21-55%) decrease in the average number of NBMA-induced esophageal tumors after 20 and 27 weeks of the bioassay. EA exhibited inhibitory effects toward preneoplastic lesions as well as neoplastic lesions. Tumors were not observed in vehicle-control rats or in rats that received EA alone.