Glucagon, a hormone secreted from the alpha cell of the endocrine pancreas, is a major counterpart to insulin. After released into blood, glucagon will combine with its receptor in targeting tissues and form a compound, which then activates its signaling pathway, produces cAMP, promotes gluconeogenesis and glycogenolysis and inventually increases blood glucose. Researches recently display that it will be an important addition to treatment method by inhibiting synthesis and secretion of glucagon, neutralizing circulating glucagon, using glucagon receptor antagonists and prohibiting gene expression of glucagon receptor.