Objective:To explore the effect of Wulong Dan (WLD) on treatment of acute cerebral infarction and change of hormones in hypothalamus-pituitary-thyroid axis. Methods:Thirty five cases of the treated group treated with WLD by taken orally and 31 cases of the control group treated with nimoton taken orally. And dextran was given intravenously to both groups. Blood level of triiodothyronine (T3), free triiodothyronine (FT3), thyroxine (T4), free throxine (FT4) and thyroid stimulating hormone (TSH) of all patients were determined before and after treatment by radioimmunoassay. Results: After 4 weeks of treatment, there were significant difference between the treated group and the control group in cure rate, markedly effective rate,cure score and disappearance of clinical symptoms (P < 0. 01 ). The levels of T3, FT3,TSH of all patients were lower than those of the normal control before treatment. After treatment with WLD and dextran, the abovementioned indexes turned to normal. Conclusions: WLD has a significant effect on patients with cerebral infarction on the basis of improved microcirculation induced by dextran. It also has regulatory effect on the hypothalamuspituitary-thyroid axis disorder so as to be helpful in maintaining the homeostasis. Objective:To explore the effect of Wulong Dan (WLD) on treatment of acute cerebral infarction and change of hormones in hypothalamus-pituitary-thyroid axis. Methods:Thirty five cases of the treated group treated with WLD by taken orally and 31 cases of the Blood group of triiodothyronine (T3), free triiodothyronine (FT3), thyroxine (T4), free throxine (FT4) and thyroid stimulating hormone (TSH) of all Patients were determined before and after treatment by radioimmunoassay. Results: After 4 weeks of treatment, there were significant difference between the treated group and the control group in cure rate, markedly effective rate, cure score and disappearance of clinical symptoms (P < 0. 01 ). The levels of T3, FT3,TSH of all patients were lower than those of the normal control before treatment. After treatment with WLD and dextran, the abovementioned indexes turned to normal. Conclusions: WLD has a significant effect on patients with cerebral infarction on the basis of improved microcirculation induced by dextran. It also has regulatory effect on the hypothmusmusuituitary-thyroid axis disorder so as to be helpful in maintaining the homeostasis.