Male breast cancer is rarer, with early tumor metastasis and poorer prognosis. Male breast cancer has a rising trend in recent years, and its incidence rate is 1%-2% of female breast cancer, and the general age of onset is around 60 years old. The cancer mostly occurs on one side, initially a small painless lump with unclear boundaries is seen under the nipple or areola, and grows rapidly in a short period of time, with faster development than female breast cancer. Symptoms of male breast cancer are mainly painless lumps under the areola, 20% of patients have nipple invagination, the boundary of the lump is often unclear, there are often skin or pectoral muscle adhesions in the early stage, and the rate of axillary lymph node metastasis is higher. The pathological manifestation of male breast cancer is similar to that of female breast cancer, most of them are invasive ductal carcinoma, but there is no lobular tissue in male breast, so there is no report of lobular carcinoma in situ in pathology. The treatment of male breast cancer is basically the same as that of female breast cancer, but because male breast tissue is smaller and it is easy to invade the pectoral muscle at an early stage, surgery should be mainly radical or extended radical surgery; for advanced or recurrent cases, the effect of endocrine therapy is better than that of female breast cancer. The main treatment method is bilateral orchiectomy, with an efficiency of 50% to 60%. Chemotherapy and radiotherapy will be considered depending on the situation.