Iron-deficiency anemia (IDA) is the most common nutritional deficiency in childhood throughout the world. Although it has been shown that IRA is associated with elevated plasma copper and depleted zinc levels in children, there are conflicting results on the effect of iron supplementation on the absorption of these elements. The aim of this study was to investigate the effects of ferrous and ferric iron supplementation on the trace element status in children (n=25, aged 8-168 mo) with IDA. Fourteen of them were treated with ferric hydroxide-polymaltose complex (Ferrum, Vifor, Switzerland) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance); the others were treated with a ferrous sulfate complex (FerroSanol, Schwarz, Germany) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance). Plasma copper, zinc, and ceruloplasmin levels as well as hematological parameters were determined at baseline and the first, third, and sixth month of the treatment period. The hemoglobin and iron levels of patients in both groups were higher in the first and sixth months compared to baseline. Although the ceruloplasmin levels were depleted (48.9 mg/dL vs 41.4 mg/dL, p=0.035) during ferrous iron treatment, the copper and zinc levels remained unchanged. On the other hand, ferric iron supplementation led to an increase in zinc levels in the sixth month of treatment (0.77 mg/L vs 1.0 mg/L, p=0.021). The plasma copper levels were lower in the ferrous iron-treated group at the end of the first month of treatment than in the ferric iron-treated group (1.06 mg/L vs 1.29 mg/L, p=0.008). In conclusion, our data showed that copper and ceruloplasmin metabolisms were affected by ferrous iron supplementation, whereas ferric iron kept them to normal levels of zinc, possibly by affecting their absorption. We conclude that the copper and zinc status of patients with IDA should be taken into consideration before and after iron therapy.