In order to evaluate the prevalence of anemia in infants under one year of age and ascertain the main etiologic factors, a survey was conducted in Moundou, Chad at the end of the rainy season. Tests were performed in 144 infants to determine hemoglobin levels, mean erythrocyte volume, transferrin saturation coefficient, serum iron level, Plasmodium positivity on blood smears, and nutritional status according to GOMEZ. Using the criteria defined by the World Health Organization, 139 infants were diagnosed as anemic including 19 cases classified as severe (hemoglobin level less than 5 g/dl). In addition, 32 of the 141 infants studied (22.7%) presented iron deficiency confirmed by two positive indicators. Serology demonstrated malaria in 45% of infants. Mean hemoglobin levels were significantly lower in infants with positive blood smears and this lowering increased the higher serum parasite levels. Nutritional status was directly correlated with hemoglobin level. This data suggests that malaria plays a major etiologic role in anemia in infants particularly severe anemia. This finding justifies use of antimalarial chemoprophylaxis in infants and the Centers for the Extended Vaccination Program provide the framework.