Oral glucose tolerance tests were carried out with methanolic extract of Abroma augusta aerial parts (leaves and stems) in glucose-loaded mice. The extract at doses of 50, 100, 200 and 400 mg per kg body weight dose-dependently and significantly reduced blood glucose levels in hyperglycemic mice by 40.2, 40.7, 41.9, and 45.4%, respectively. A standard antihyperglycemic drug, glibenclamide, when administered to hyperglycemic mice at a dose of 10 mg per kg reduced blood glucose level by 41.9%. Thus the studies reveal that the extract possess considerable antihyperglycemic activity and can possibly be used to lower high blood glucose levels present in disorders like diabetes.