Abstract：Objective：To observe the clinical effect of modified Danggui Sini tang combined with western medicine for patients with thromboangiitis obliterans(TAO). Methods： A total of 90 cases of TAO patients with cold congealing in the collaterals syndrome were divided into the observation group and the control group according to the random number table method，45 cases in each group. Both groups were treated with aspirin enteric- coated tablets，nicardipine hydrochloride tablets and alprostadil injection， and patients with intolerable pain can take ibuprofen tablets. The observation group was additionally given oral administration of modified Danggui Sini tang. Both groups were treated for three months. Before treatment and after three-month treatment，the scores of the five main symptoms and signs including cold extremities，limb numbness，intermittent claudication，limb color and rest pain were evaluated，the ankle brachial index(ABI) was evaluated and intermittent claudication distance was recorded. The clinical effect was evaluated in the two groups. Results： After treatment，the clinical effect in the observation group was better than that in the control group(P＜0.05). The intermittent claudication distances in the two groups were increased when compared with those before treatment(P＜0.01)，ABI were increased(P＜0.01). The intermittent claudication distance in the observation group was more than that in the control group(P＜ 0.01)，ABI was higher(P＜0.01). The scores of cold extremities，limb numbness，intermittent claudication，limb color and rest pain in the two groups were decreased when compared with those before treatment(P＜0.01)，and the above five scores in the observation group were lower than those in the control group(P＜0.01). Conclusion： Based on routine western