Background and Objectives: The favourable effects of coffee on liver enzymes have been reported worldwide. This study investigated the association between coffee consumption and serum aminotransferase concentration in Korean adults. Methods and Study Design: Data were obtained from the fourth and fifth Korea National Health and Nutrition Examination Surveys. Elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) concentration were defined as >30 IU/L for men and >19 IU/L for women. The risk of elevated ALT and AST according to general characteristics and frequency of coffee consumption were tested by chi-square tests and multiple logistic regression analyses. Results: The prevalence of elevated ALT was 27.4%, 27.8%, and 26.9% in subjects who drank <1, 1, and ≥2 times/day, respectively. The proportions of individuals with elevated AST were 32.5%, 33.1%, and 26.7% in subjects who drank <1, 1, and ≥2 times/day, respectively. The aORs for elevated ALT and AST were significantly lower in subjects who drank ≥2 times of coffee/day than in those who drank <1 time/day (ALT: aOR=0.86, 95% CI=0.79-0.94; AST: aOR=0.83, 95% CI=0.76-0.91). In subgroup analysis, con- sumption of ≥2 times/day was associated with lower ORs for elevated ALT in the high-risk group overall and in the viral hepatitis and obesity subgroups, respectively. In sensitivity analysis, reduced frequency of coffee con- sumption was associated with an increased risk for elevated liver enzymes, although an association between cof- fee consumption and elevated ALT was not observed in women or current smokers. Conclusions: Higher coffee consumption was associated with lower risk of elevated aminotransferase concentration in Korean adults.