Glucagon is a secreted protein and belongs to the glucagon family. Glucagon can be cleved into 8 chains, playing an important role in initiating and maintaining hyperglycemic conditions in diabetes. Glucagon can regulates blood glucose by decreasing glycolysis and increasing gluconeogenesis. In addition, Glucagon is involved in initiating and maintaining hyperglycemic conditions in diabetes. Glucagon release is stimulated by hypoglycemia and inhibited by hyperglycemia, insulin, and somatostatin. In the glucagon antagonist, His-53 and Phe-58 are missing. This antagonist has been successfully utilized to reduce glucose concentration in vivo.