Effects of mahwang(Ephedrae herba) aqua-acupuncture at sinsoo (B-23)and Jisil(B-52)on adrenal cortical insufficiency were investigated in dexamethasone treated rats. Concentration of serum cortisol was decreased in dexamethasone treated rats. However, these values showed a tendency to increase in mahwang(Ephedrae herba) aqua-acupuncture groups. Concentration of serum total protein was increased in dexamethasone treated rats. However, these values were decreased by the mahwang(Ephedrae herba) aqua-acupuncture. The portion of neutrophils was decreased and the portion of lymphocytes and eosinophils were increased in dexamethasone treated rats. However, in mahwang(Ephedrae herba) aqua-acupuncture groups, the portion of neutrophils showed a tendency to increase and the portion of lymphocytes and eosinophils showed a tendency to decrease. In dexamethasone treated rats, the weight of adrenal glands were decreased, however these values were increased in mahwang(Ephedrae herba) aqua-acupuncture groups.