Abstract： Objective： To observe the clinical effect of the therapy of modified Danggui Liuhuang tang combined with methimazole tablets on hyperthyroidism of the type of yin deficiency resulting in vigorous fire. Methods：A total of 140 cases with hyperthyroidism of the type of yin deficiency resulting in vigorous fire were randomly divided into the control group and the observation group according to number table method， 70 cases in each group. The control group was treated with methimazole tablets，and the observation group was additionally treated with the therapy of modified Danggui Liuhuang tang combined with methimazole tablets. The changes of levels of thyroid hormone， symptom scores and quality of life were compared between the two groups before and after treatment. Results：After treatment，the scores of main symptoms， secondary symptoms and the total score in the two groups were decreased when compared with those before treatment(P＜ 0.05)，and the above scores in the observation group were lower than those in the control group(P＜0.05). After treatment， free triiodothyronine(FT3) and free thyroxine(FT4) levels in both groups were decreased when compared with those before treatment(P ＜ 0.05) ， and the thyroid-stimulating hormone(TSH) levels in both groups were increased(P ＜ 0.05) ； the improvement of the above levels in the observation group was more significant than that in the control group(P＜0.05). After treatment，the scores of physical function，social function，material life，mental function and total scores in the two groups were improved when compared with those before treatment(P＜0.05)，and the above scores in the observation group were higher than those in the control group(P＜0.05). Conclusion：The therapy of modified Danggui Liuhuang tang combined with methimazole tablets has a significant therapeutic effect on the treatment of hyperthyroidism of the type of yin deficiency resulting in vigorous fire，which can reduce FT3 and FT4 levels，and improve clinical symptoms and the quality of life.