As indicators of obesity, waist circumference (WC), body mass index (BMI), and adiponectin are well-known risk factors for diabetes mellitus. The objectives of this study were to measure the independent association between these obesity indicators and diabetes and to examine the combined effect of these indicators on diabetes in a Korean population. The WC, BMI, and serum adiponectin were measured in 4459 healthy Koreans and were classified into tertile groups for men and women. The independent and combined associations of the obesity indicators with diabetes were measured using logistic regression analyses. Diabetes was defined as fasting serum glucose greater than 126 mg/dL or taking medication. Levels of adiponectin were inversely associated with BMI and WC and directly associated with age and high-density lipoprotein (HDL) cholesterol (P < .001). After adjusting for age, BMI, WC, and other lifestyle factors, low levels of adiponectin were associated with an increased prevalence of diabetes. Further adjustment for HDL cholesterol and triglyceride attenuated this association in women but not men. The combined effects of WC and adiponectin on diabetes progressively increased; however, the interaction of these 2 variables was not statistically significant. The combined effect of BMI and adiponectin on diabetes showed similar results. These results suggest that adiponectin was associated with diabetes. The association was independent of BMI and WC and was partly modified by HDL and triglyceride. There were no effect modifications of adiponectin with WC and BMI on diabetes.