Abstract： Objective： To observe the clinical effect of Sanjie Xiaopi Decoction combined with Tamoxifen Citrate Tablets on patients with mammary gland hyperplasia of liver constraint and phlegm coagulation type. Methods：A total of 80 cases of female patients with mammary gland hyperplasia of liver constraint and phlegm coagulation type were divided into the combination group and the control group according to the random number table method，with 40 cases in each group. The control group was treated with Tamoxifen Citrate Tablets， and the combination group was treated with Sanjie Xiaopi Decoction combined with Tamoxifen Citrate Tablets. Both groups were continuously treated for two courses. Traditional Chinese medicine (TCM)syndrome scores， breast lump scores (including three scoring indicators： the size， range， and texture of lumps)， and breast pain scores [Visual Analogue Scale (VAS) score] were evaluated before and after treatment. Endocrine hormone indicators [estradiol (E2)， luteinizing hormone (LH)， progesterone (P)， and prolactin (PRL)] were detected. Clinical effects were compared between the two groups. Adverse reactions during treatment were observed and recorded. Results：After treatment，the total effective rate in the combination group was higher than that in the control group (P＜ 0.05). The scores of breast tenderness，the tendency to depression and irascibility，chest oppression and rib-side distension， vexation， bitter taste， and insomnia and profuse dreaming in the two groups were decreased when compared with those before treatment (P＜0.05)， and the above six scores in the combination group were lower than those in the control group (P＜0.05). The scores of size， range， and texture of breast lumps， as well as VAS scores of breast pain in the two groups were decreased when compared with those before treatment (P＜0.05)，and the above four scores in the combination group were lower than those in the control group (P＜0.05). The levels of E2，LH，and PRL in serum in the two groups were declined when compared with those before treatment (P＜0.05)，and serum P levels were increased when compared with those before treatment (P＜0.05)； the levels of E2， LH， and PRL in serum in the combination group were lower than those in the control group (P＜0.05)， and serum P level in the combination group was higher than that in the control group (P＜0.05). No obvious adverse reaction occurred in the two groups during treatment. Conclusion：Sanjie Xiaopi Decoction combined with Tamoxifen Citrate Tablets has better curative effects in the treatment of patients with mammary gland hyperplasia of liver constraint and phlegm coagulation type，which can effectively soften and dissipate breast lumps，alleviate breast pain and related symptoms，and regulate hormone levels，with high safety.