Physiological activities of hot water extract and solvent fractions isolated from Astragalus membranaceus were examined and the antioxidative, fibrinolytic, thrombin inhibitory and a-glucosidase inhibitory activity were measured. The hot water extract of Astragalus membranaceus was fractionated into hexane, chloroform, ethyl acetate, butanol and water fractions, and each of these fractions was individually assayed. The antioxidative activities of ethyl acetate and chloroform fractions were 89.96% and 87.36%, respectively. Using the fibrin plate method, only the hot water extract showed a plasmin activity of 0.41 units/ml. The thrombin inhibitory activity of the ethyl acetate fraction was the highest with a value of 82.73%. The hot water extract displayed a-glucosidase inhibitory activity of 64.91%. In conclusion, the hot water extract and the ethyl acetate fraction can be used as materials for the development of biofunctional foods to prevent cardiovascular diseases.