A breast abscess can be considered as a disease or as a manifestation of another disease. A breast abscess is in fact a symptom of the development of mastitis, a regression in the process of mastitis development. When the necrotic tissue caused by mastitis gathers around the milk ducts, causing necrotic alienation and abscess, it is actually not a disease, but a regression of the disease, a symptom. Breast abscess is mainly caused by mastitis, and most instructors do not speak about the definition of breast abscess, which is just a manifestation of mastitis. Mastitis can be divided into lactating and non-lactating mastitis, and lactating mastitis has a more acute onset and is a type of acute abscess. Clinically, it is common to see abscesses caused by non-lactating mastitis, which are more difficult to deal with and more patients visit the hospital. Non-lactating breast abscesses are mainly caused by non-specific inflammation during the non-lactating period, and there is no clear etiology, but there are three major types of manifestations of ductal dilatation, periductal type, and non-specific nipple inflammation. The main causes are nipple invagination, ductal occlusion, and autoimmune diseases that cause inflammatory reactions that can lead to necrosis of the surrounding tissue. A large number of lymphocytes, leukocytes, and macrophages gather around the inflammation, causing tissue necrosis, and when necrosis develops to a certain extent, heterogeneity and abscesses occur, and breast abscesses occur.