Iron is an essential mineral obtained through dietary intake, required for a multitude of cellular and physiologic functions, in playing important roles in pediatric health and disease, physical growth, and development. Iron intake needs change depending on a patient’s phase of growth, sex, and pregnancy/lactation. It is required for basic cellular life-sustaining mechanisms such as DNA synthesis, cellular respiration, ATP synthesis, and the oxygen-carrying capacity of hemoglobin in erythropoiesis. In excess, iron may result in nonspecific cellular damage due to free-radical formation, its metabolism therefore requiring tight regulation through absorption, storage, utilization, and recycling. Iron’s importance in erythropoiesis makes its deficiency a common etiology of anemia, countered with optimization of oral or parenteral iron therapy. Although less common, iron-overload conditions due to primary/genetic, or secondary cause, also impact pediatric health.