Breast cancer armored chest is the breast showing diffuse dark purplish-red color, tightening of breast, skin and muscle, fixed on the chest wall and difficult to move, like wearing armor. Armored chest is one of the clinical manifestations of advanced breast cancer, which refers to the breast cancer lesions merging with each other or extensively infiltrating the whole breast, skin as well as muscles and ribs in the deeper layers of the breast, and even invading the opposite side of the chest wall and the back, resulting in the breast as well as the mass being fixed on the chest wall and difficult to move. Armored chest presents with a diffuse dark purplish-red color, and some patients may also present with skin cancerous nodules and skin ulcers. The tightness of the chest wall caused by armored chest can lead to discomfort in the chest wall, and some patients may even have difficulty breathing. Generally speaking, advanced breast cancer with armored chest is difficult to be treated by surgery, and it needs respiratory support, chemotherapy, radiotherapy and endocrine therapy to prolong the survival period and improve the quality of life, etc. Her-2 positive patients can also be added with targeted therapy.