Obesity occur from the imbalance between energy intake and energy expenditure. Obesity is a complex chronic disease that is suggested to cause other metabolic disorders such as type 2 diabetes, hyperlipidemia, hypertension, and arteriosclerosis. In this study, our purpose is to investigate the anti-hyperglycemic and anti-obesitic effects of Maydis stigma water extract in 3T3-L1 adipocytes and db/db mice. Maydis stigma water extract at dose of 100 and 500 ${mu}g/ml$ slowly inhibited cell viability as compared to that of control in mature adipocytes. Also, the additions of 50 and 250 ${mu}g/ml$ of Maydis stigma water extract significantly inhibited the lipid accumulations and CCAAT/enhancer-binding protein(C/EBP) ${alpha}$ and peroxisome proliferator-activated receptor(PPAR) ${gamma}$ expressions with dose-dependent manner in 3T3-L1 adipocytes. Maydis stigma water extract at 250, 500, and 1000 ${mu}g/ml$ only showed the increasing pattern on lipolysis activity. The oral treatment of Maydis stigma water extract (100 or 400 mg/kg body weight) in db/db mice only showed tendency to decrease body weight, food efficiency ratio (FER), HbA1c, blood glucose, total cholesterol, triglyceride, and the adipocyte size of in db/db mice. However, Maydis stigma water extract increased the insulin level in a dose dependent manner. Thus these results indicate that Maydis stigma water extracxt inhibits adipogenesis through regulation of C/EBP${alpha}$ and PPAR${gamma}$ expressions in 3T3-L1 adipocytes and shows anti-hyperglycemic effect through increase of insulin secretion in db/db mice.