The production of free radicals can cause renal injury and play a role in the pathogenesis of acute renal failure (ARF). The indirect markers of reactive oxygen species (ROS) were evaluated in children with ARF and controls. Forty patients with ARF aged 0-10 years were selected. Twenty age- and gender-matched healthy children were included as controls. Plasma malondialdehyde, protein carbonyl, nitrite, copper, ascorbic acid, zinc, and ceruloplasmin levels were estimated in patients with ARF and controls. The plasma malondialdehyde (p < 0.01), copper (p < 0.001), ascorbic acid (p < 0.05), and ceruloplasmin (p < 0.001) levels were significantly raised in ARF patients in comparison with controls. Significantly higher levels of plasma malondialdehyde (p < 0.01), nitrite (p < 0.001), copper (p < 0.001), and ceruloplasmin (p < 0.001) and lower plasma zinc (p < 0.01) were found in ARF nonsurvivors in comparison with survivors. The cutoff levels of plasma nitrite and ceruloplasmin were found to be most accurate in predicting mortality in ARF patients and had maximum sensitivity (100%) and specificity (60.7%) among the parameters studied. In conclusion, the increased levels of oxidants and antioxidants suggest the production of ROS and their possible role in ARF pathogenesis. Plasma nitrite and ceruloplasmin concentrations demonstrated predictive ability in relation to mortality.