This study was aimed to verify the anti-diabetic activity of Kangdangboeumbang(KBB) in NOD mice which is Insulin Dependent Diabetes Mellitus(IDDM). The reduction of blood glucose after oral administration between 14 weeks by 2 weeks period to a NOD mice in KBB extract treatment group was showed from 7 day after comparing with control group. KBB extract treatment group increasd insulin secretion amount of serum than control group and decreased IFN­γ production. The pancreatic β-cells is destroyed by Th1-dependent autoimmune disease in NOD mice. KBB extract treatment group intercepted the progress of edematous islet controlling inflammatory mononuclear cells of infiltration that also destruction of pancreatic β-cells electively in a NOD mice.