Hemoglobin(Hb) is the main component of the blood proteins, and it is consisted of globin and hemin.Hemoglobin and its derivatives are rich in iron and amino acids, which can be used in food as coloring agents, emulsifiers, iron supplements and other supplements. With the sensitivity to light, lack stability, and unpopular smell, the hemoglobin was limited in processing and application. This paper reviewed the preparation methods and the application of hemoglobin and its derivatives in food, to provide refe...