To investigate the effects of Cantharidis Capsule on the quality of life of the patients with breast cancer endocrine therapy. Methods:A total of 126 patients who received radical mastectomy from May 2015 to June 2017 were selected as the subjects. They were randomly divided into 63 cases in the control group and 63 cases in the observation group. The control group was given endocrine drug treatment. The observation group was treated with pure Chinese medicine preparation of Cantharidin Capsule on the basis of the control group. The quality of life, immune function changes and adverse reactions during treatment were observed in the two groups before and after treatment. Results:There was no significant difference in the quality of life between the two groups before treatment (P > 005). After treatment, the scores of FACT-B and EORTC-QOL-C30 in the observation group were significantly higher than those in the control group. The difference was statistically significant (P<005). There was no significant difference between the two groups before treatment (P>005). After treatment, the CD8+ in the observation group was significantly lower than that in the control group, and CD4+ and CD4+/CD8+ were significantly higher than those in the control group. The difference was statistically significant (P<005). The incidence of nausea, fever, muscle joint pain and vaginal bleeding in the observation group were 1111%, 794%, 635% and 317%, respectively, which were significantly lower than those in the control group 2540%, 2063%, 1905% and 1429% (P<005). Conclusion:Adding Cantharidin capsule to endocrine therapy of breast cancer can effectively improve the immune function, reduce adverse reactions and improve the quality of life, and is worthy of promotion.