Anemia in premature infants can be prevented by prophylactic treatment with recombinant human erythroprotein (r-huEPO). r-HuEPO as been used for a long time in patients with end-stage renal failure. The main factor which can limit r-HuEPO efficiency is limited iron bioavailability. Adapted iron supplementation is needed when preterm infants receive r-HuEPO in order to avoid the depletion of iron stores. Oral iron supplementation is simple but indigestibility is frequent. Furthermore, the intestinal absorption and utilization of oral iron is limited. Parenteral iron supplementation is possible in infants who are very pre-term as they are parenterally fed during the first weeks of life. There are various preparations of intravenous iron with different physicochemical properties. Toxicity and side-effects of parenteral iron preparations depend on these properties. Two parenteral iron preparations are available in France: iron-saccharate (Venofer) and iron-dextrin (Maltofer). Iron delivery and possible side-effects of these preparations are different and need to be considered before use in preterm infants.