Background: Congenital cyanotic heart disease (CCHD) patients experience hypoxia, which stimulates erythropoiesis and polycythemia, increasing iron consumption and depleting iron reserves. The ensuing iron deficiency anemia (IDA) is made worse by hype viscosity because microcytic erythrocytes, which are resistant to deformation in the microcirculation, are present. As a result, cyanotic episodes and cerebrovascular accidents occur more frequently. Aim: The present study aims to assess the iron profile and detect the prevalence of IDA in patients with CCHD admitted to the Cardiology Unit at Assiut University Children's Hospital (AUCH) for one year. Patients and Methods: 75 patients with CCHD participated in the one-year descriptive cross-sectional study conducted at the AUCH cardiology unit from January 1 through December 31, 2021. A complete blood count (CBC) with differential count and retics, serum iron, total iron binding capacity (TIBC), serum ferritin, and transferrin saturation were all performed on these patients. The patients with CCHD were split into groups, Group A (non-iron deficient group, n=56) and Group B (iron deficient group, n=19), based on the serum ferritin level. Results: The median age of the studied cases was seven months, ranging from one month and a half up to 11 years old. The older the patients with uncorrected CCHD, the more likely they will have IDA (P=0.014). According to the serum ferritin level, we divided the 75 children with CCHD into Group A (non-iron deficient group, n=56) and Group B (iron deficient group, n=19). According to their blood ferritin levels, in the current study, iron deficiency was present 25.3% of the time in children with CCHD. Serum iron and transferrin saturation, as well as Mean corpuscular volume (MCV), Mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC), were all considerably lower in the iron-deficient group than in the non-iron-deficient group (P0.05). The median blood ferritin level of the iron-deficient group ranged from 12.0 (1.0 - 25.0) ng/mL to 106.0 ng/mL in the non-iron-deficient group (22.0 - 288.3). (P 0.001). Conclusion: IDA is significantly more prevalent in CCHD patients