In this study, the effects of Gamgung-tang gamibang on the hyperthyroidism induced by the intraperitoneal injection of 3,5,3-triiodothyronine was examined by the measurement of physical changes, body weight, the volume of food intake and rectal temperature, and heart weight, heart beat, blood pressure with contrast to propranolol, one of beta-blocking agents. the obtained results were as follows. The Gamgung-tang gamibang extract showed to inhibit the decrease of body weight and rectal temperature, and decrease the food intake, so the inhibitory effects of Gamgung-tang gamibang extract on the experimental hyperthyroidism were exhibited. The Gamgung-tang gamibang extract showed the inhibitory effects on the circulatory functions changed and enhanced by the experimental induced hyperthyroidism, the action of Gamgung-tang gamibang extract was less effective than the propranolol of D-CONT group. The Gamgung-tang gamibang extract showed significant effects to inhibit the concentration of serum thyroid houmone, more effective than the propranolol, beta-blocking agents. The Gamgung-tang gamibang extract showed the effective inhibitory reaction on the biochemical changes in serum, cholesterol, ketone bodies, free fatty acid, glucose in hyperthyroid rats induced by 3,5,3-triiodothyronine.