BACKGROUND: Low grade inflammation has been proposed as a pathophysiologic mechanism of obesity. Thus, we sought to determine the relation of C-reactive protein to obesity in Korean children. METHODS: We selected 585 children aged 9 years in Seoul. Anthropometric measurements and fasting blood samples were collected and body mass index (BMI) was calculated as weight/height2. We measured high-sensitivity CRP (hs-CRP), glucose (FBS), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), and triglyceride (TG). RESULTS: Hs-CRP concentration was positively correlated with weight, BMI, waist circumference and negatively correlated with HDL-C. On multivariate analysis, these variables emerged as independent determinants of hs-CRP concentration. CONCLUSION: Obesity is associated with higher hs-CRP concentration. These findings suggest a state of subclinical inflammation in obese children.