Abstract: Occult breast cancer is a rare type of breast cancer with metastasis in the axillary lymph nodes as the first sign. For these patients, a thorough preoperative clinical evaluation should be performed including standard radiographic imaging with bilateral mammography and ultrasound and magnetic resonance imaging of the breast. Simple observation of the breast is not recommended due to high rate of loco-regional recurrence. Treatment for occult breast cancer includes mastectomy or breast-conserving therapy combined with irradiation to the whole breast. Axillary lymph node dissection should be performed in order to obtain better local control and complete staging information. Further, patients can also be treated with systemic adjuvant chemotherapy. Although occult breast cancer is considered as T0N1/2M0 disease, the progno -sis appears to be more favorable than that in those with stage Ⅱbreast cancer. The number of positive lymph nodes re-mains the most reliable predictor for the prognosis of occult breast cancer.