Introduction: The iron deficiency anemia (IDA) is the most common micronutrient malnutrition in the world. This condition has been shown to increase morbidity in adults and to exert negative impact on the psycho-motor development in children. The IDA in children with congenital heart disease (CHD) with its negative consequence has been recognized for a long time but in clinical practice the issue does not gain sufficient attention in developing countries.Objectives: We conducted this study to investigate the prevalence of IDA in children with CHD and to assess the diagnostic values of hemogram, especially the erythrocyte indexes as a simple tool for early recognition of IDA. Materials and methods: Children under 15 years old with confirmed CHD admitted to were recr uited. The total blood cell count, serum iron, ferritin and transferrin were measured preoperatively.Results: There were 69 pediatric patients were recruited in which 36 children with cyanotic CHD and 33 children with acyanotic CHD. There were 11.1% of children with cyanotic CHD and 3% of children with acyanotic CHD who showed true IDA. The prevalence of depletion or reduction of body iron store was very high. Up to 77.8% of children with cyanotic CHD and 87.2% children with acyanotic CHD were at risk of iron deficiency. The erythrocyte indexes proved to be useful as simple tool for detecting IDA in children with cyanotic CHD.Conclusion: IN the present investigation, the prevalence of IDA was found high in the children with CHD. The total blood cell count and erythrocyte indexes were of suggestive value for diagnosis of IDA. Iron supplement treatment should be recommended in this group of patients. AbstractIron deficiency anemia in children with congenital heart disease and the usefulness of erythrocyte indexes as a screening tool.