Adjuvant chemotherapy is an important tool and part of the comprehensive treatment of breast cancer. A suitable postoperative adjuvant chemotherapy regimen can control bloodstream metastasis to significantly reduce the risk of recurrence and improve the survival rate of patients with breast cancer. If the indications for chemotherapy are clear, the choice of chemotherapy drugs, the combination and sequence of drugs to be used, and how to use them appropriately without overdoing them are always difficult clinical choices. After decades of research, there are more than 20 types of chemotherapeutic drugs that have been proven to be more effective for breast cancer, and there are many combination regimens. Among them, highly effective drugs with efficiency up to about 50% include adriamycin, paclitaxel (paclitaxel, Tysol, Tysudy, Zithromax), Noviben, etc. Moderately effective drugs with efficiency of 20-50% include cisplatin, cyclophosphamide, fluorouracil, methotrexate, mitomycin, vincristine, etc. The common regimens of adjuvant chemotherapy for breast cancer are described as follows. 1.CMF regimen CMF regimen is the first adjuvant chemotherapy regimen used for postoperative breast cancer. The classical CMF regimen includes CTX, MTX, 5-FU. day 1 and 8, repeated every 4 weeks. Although an anthracycline-containing combination chemotherapy regimen is currently considered superior to CMF, it does not negate its role in adjuvant chemotherapy, and it is still an ideal option for low-risk patients, elderly patients with cardiovascular disease, or those allergic to anthracyclines. 2.Anthracycline-containing combination chemotherapy regimens Commonly used regimens include CAF (CTX+ADM+5-FU), CEF (CTX+EPI+5-FU), and AC (ADM+CTX). Anthracycline regimens are currently considered superior to CMF regimens, and a 4-cycle anthracycline-containing combination chemotherapy regimen has comparable efficacy to the full 6-week CMF regimen. For low-risk patients, 4 cycles of CEF regimen or AC regimen can be given after surgery, and 6-cycles of chemotherapy are still required for high-risk patients. 3.Paclitaxel-containing combination chemotherapy regimen Due to the outstanding efficacy of paclitaxel drugs in the treatment of advanced breast cancer, they have been used for postoperative adjuvant chemotherapy since the mid-1990s. Currently, paclitaxel-containing chemotherapy regimens have been more widely used for postoperative adjuvant chemotherapy for breast cancer, especially for cases with positive axillary lymph nodes, in the hope of obtaining better clinical efficacy. 4.Trastuzumab-containing combination chemotherapy Trastuzumab is a targeted monoclonal antibody used to treat Her-2 high expression advanced breast cancer in recent years, and has achieved very good efficacy in combination with chemotherapy. 5.Other regimens include adjuvant chemotherapy with platinum-containing regimens and adjuvant chemotherapy with new drugs such as capecitabine, vincristine (Novibrium) and gemcitabine. Currently, they are mostly used as second-line drugs for cases that are resistant to first-line drugs or are more advanced and have metastasized and spread. In conclusion, the choice of adjuvant chemotherapy regimens for breast cancer should weigh the risk of recurrence, the risk of possible toxicity from treatment and the benefit for each patient. The priority postoperative adjuvant chemotherapy regimen should be considered according to the patient’s hormone receptor status and HER2 status as well as the different classifications of breast cancer, reflecting the principle of individualization.