We compared the levels of hepatic enzymes in 220 Japanese men with metabolic syndrome with those in age and sex-matched subjects without the syndrome. Metabolic syndrome was defi ned by the new criteria published in Japan, and hepatic enzymes, i.e., aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (gammaGTP), were measured. AST, ALT and gammaGTP in subjects with metabolic syndrome were significantly higher than those in subjects without the syndrome, and metabolic syndrome was closely associated with hepatic enzymes in this cohort of Japanese men.