Background: Sialic acid (SA) has been shown to be a strong predictor of cardiovascular mortality in adults. No study in children regarding the association of SA with cardiovascular risks exists in the literature. Aim: We aimed to investigate the association of SA with anthropometric and metabolic parameters and its correlation with metabolic syndrome (MS) and carotid intima-media thickness (IMT) in obese children. Methods: A total of 154 obese children were included in the study (74 females, 80 males; mean age 11.3 ± 2.6 years). Anthropometric measurements including body fat percentage (BFP) were recorded. Fasting lipids and SA levels were measured. The carotid IMT was evaluated with ultrasonography. Results: We found a significant correlation between serum total SA (TSA) levels and BFP (r = 0.25, p = 0.01 in the whole group; r = 0.43, p = 0.00 in girls). The group with BFP ≥95th percentile had higher TSA levels than the group with BFP <95th percentile (p = 0.04). TSA and carotid IMT were weakly correlated (r = 0.20, p = 0.01), but the significance was lost after correcting for BFP. No correlations were found between TSA and other anthropometric measurements. TSA did not correlate with serum fasting glucose, lipids, insulin or homeostasis model assessment-insulin resistance. TSA levels were not different between children with or without MS. Conclusion: Serum TSA levels are significantly correlated with BFP in obese children. Copyright © 2011 S. Karger AG, Basel.