In Taiwan, breast cancer has the highest incidence among all cancers. Although adjunctive traditional Chinese medicine treatment (TCM) have been used to ameliorate the side effects or discomfort caused by cancer treatments, no study has focused on the assessment of the quality of life of patients undergoing adjunctive TCM treatments. This study compared the quality of life between breast cancer patients treated with and without adjunctive TCM. Questionnaires were collected from 7 hospitals with a Chinese medicine clinic in 2018 to 2019. Breast cancer patients who had cancer stages I, II, or III and also underwent resection surgery were included in the study. They were divided into 2 groups: patients receiving cancer treatments with adjunctive traditional Chinese medicine (TCM group) and those receiving cancer treatments without adjunctive traditional Chinese medicine (non-TCM group). A 1:1 matching was used to obtain the study participants. The EQ-5D questionnaire was used to assess the quality of life. Statistical analysis was performed using the t-test and ANOVA to compare the differences between variables. The conditional multiple regression model was applied to explore the factors associated with quality of life in breast cancer patients. A total of 543 participants were surveyed, and 450 participants were included in the study. The EQ-5D score of the TCM group (81.60 ± 11.67) was significantly higher than that of the non-TCM group (78.80 ± 13.10; P < .05). The results of a conditional multiple regression model showed that the TCM group had a higher (3.45 points) quality of life than non-TCM group (P = .002) after adjusting for other related factors. After stratifying by cancer stage, patients with cancer stages II and III scored 5.58 and 4.35 points higher in the TCM group than did those in the non-TCM group (P < .05). Breast cancer patients undergoing cancer treatment with adjunctive traditional Chinese medicine have a higher quality of life than those treated without adjunctive traditional Chinese medicine.