Tumor markers for breast cancer can be used as a diagnostic aid, mainly for the determination of carcinoembryonic antigen, but also for the determination of glycoantigens. After breast cancer surgery, tumor marker tests should be performed every six months to one year as clinical guidance, because some patients with occult breast cancer have early manifestations of elevated tumor markers in the blood. The relevant examinations, including ultrasound, CT and, if necessary, bone scan or whole-body PET-CT scan, should be completed in time to further clarify the site of recurrence or metastasis of breast cancer and to make a full reference for clinical treatment. If breast cancer patients have recurrence or metastasis, they should promptly undergo intravenous chemotherapy to control it and monitor the changes of tumor markers during the treatment.