The hepcidin is antimicrobial peptide has antimicrobial effects discover before more than a thousand years; it has a great role in iron metabolism and innate immunity. Hepcidin is a regulator of iron homeostasis. Its production is increased by iron excess and inflammation and decreased by hypoxia and anemia. Iron-loading anemias are diseases in which hepcidin is controlled by ineffective erythropoiesis and concurrent iron overload impacts. Hepcidin reacts with ferroportin. The ferroportin is found in spleen, duodenum, placenta, if the ferroportin decrease, it results in the reduced iron intake and macrophage release of iron, and using the iron which stores in the liver. Gene of human hepcidin is carried out by chromosome 19q13.1. It consists of (2637) nucleated base. HAMP gene was founded in the liver cells, in brain, trachea, heart, tonsils, and lung. Changing in the HAMP gene will produce a change in hepcidin function. The hepcidin is made many stimulators are included opposing effects exerted by pathological and physiological conditions. Hepcidin is essential for iron metabolism, understanding stricter and genetic base of hepcidin is crucial step to know iron behavior and reactions to many health statuses.