The cost of the 21-gene test is around$1,800. The incidence of breast cancer is increasing year by year, seriously jeopardizing women’s health. The current treatments for breast cancer are surgery, radiotherapy, chemotherapy and targeted drug therapy. Currently 21 gene test is mainly used for the examination of oncogenes in excised breast tissues. Through the examination of 16 main genes and 5 auxiliary genes, it can determine the condition and guide the use of medication, and at the same time, it can monitor the condition.21 gene test has been increasingly valued by the majority of clinicians and breast cancer patients. At present, genetic testing plays a role in more fields, and 21 gene testing also plays a very important role in the prevention and treatment of breast cancer in women.