AIM: To study the levels of adiponectin in nondiabetic patients with nonalcoholic fatty liver disease (NAFLD) in comparison with control group. METHODS: Thirty-five patients who had elevated serum aminotransferase levels with bright liver and 34 healthy volunteers without liver disease were evaluated. Age, gender and body mass index (BMI) were recorded. Fasting plasma glucose, insulin, adiponectin, proinsulin and lipid profile were measured. A standard oral glucose tolerance test (OGTT) with insulin response was performed and the index of insulin resistance was calculated according to the homeostasis model assessment (HOMA) method. RESULTS: According to the OGTT results, none of the participants had diabetes. Serum adiponectin levels were statistically significantly lower in patients with NAFLD than in control group (8.14±3.4μg/mL vs 12.4±9.4μg/mL, respectively, P<0.01). A statistically significant correlation was found between adiponectin and BMI (r: -0.33, P<0.01), HOMA (r: -0.26, P<0.05), proinsulin (r:-0.32, P<0.01), AST (r: -0.25, P<0.05), ALT (r: -0.26, P<0.05) or GGT (r: -0.22, P<0.05). In multiple regression analysis models, adiponectin levels were the only predictor of NAFLD in males, whereas in female group it was the BMI. CONCLUSION: Low adiponectin level might be a predictor of NAFLD especially in male nondiabetics. AIM: To study the levels of adiponectin in nondiabetic patients with nonalcoholic fatty liver disease (NAFLD) in comparison with control group. METHODS: Thirty-five patients who had elevated serum aminotransferase levels with bright liver and 34 healthy volunteers without liver disease were evaluated. Fasting plasma glucose, insulin, adiponectin, proinsulin and lipid profile were measured. A standard oral glucose tolerance test (OGTT) with insulin response was performed and the index of insulin resistance was calculated RESULTS: According to the OGTT results, none of the participants had diabetes. Serum adiponectin levels were statistically significantly lower in patients with NAFLD than in control group (8.14 ± 3.4 μg / mL vs 12.4 ± 9.4μg / mL, respectively, P <0.01). A significant correlation was found between adiponectin and BMI (r: -0.33, P <0.01) (R: -0.25, P <0.05), proinsulin (r: -0.32, P <0.01), AST <0.05). In multiple regression analysis models, adiponectin levels were the only predictor of NAFLD in males, but in female group it was the BMI. CONCLUSION: Low adiponectin level might be a predictor of NAFLD especially in male nondiabetics.