The relationship between inflammation, oxidant stress and cardiovascular damage in children with chronic renal failure (CRF) has not previously been investigated. The aim of this study was to investigate markers of oxidative stress, inflammation and early cardiovascular abnormalities. Therefore, erythrocyte superoxide dismutase (SOD) and catalase (CAT) activities; blood glutathione (GSH) and serum malondialdehyde (MDA) levels; C-reactive protein (CRP) and proinflammatory cytokines (IL-6, TNF-alpha,); and left ventricular masses (LVM) and intima media thicknesses (IMT) were measured in children with CRF. A total of 29 children with CRF (19 nondialysis, 10 peritoneal dialysis) were included. The control group consisted of 25 healthy subjects. CRF children had significantly increased IL-6, TNF-alpha, CRP and MDA concentrations and decreased SOD, CAT and GSH levels compared with controls (P < 0.05). Nondialysis and peritoneal dialysis subgroups had similar oxidative stress and inflammation biomarkers (P > 0.05). Erythrocyte CAT was positively correlated with CRP, TNF-alpha, and IL2-R in the study group. Positive correlations were found between cytokine concentrations, CRP and urea/creatinine levels. Significantly increased LVM and IMT values were found in CRF children (P < 0.05). In conclusion, increased oxidant stress and inflammation together with early cardiovascular damage were found in CRF children. Further studies with more patients are needed to verify these results.