The cause of breast cancer is not fully understood, so there is no definite method to prevent breast cancer. From the analysis of epidemiological survey, the prevention of breast cancer can be considered in the following aspects: 1. Establish a good lifestyle, adjust the rhythm of life, and keep a relaxed mood. 2.Adhere to physical exercise, actively participate in social activities, avoid and reduce mental and psychological tension factors, and keep a calm mind. 3.Cultivate good eating habits. Pay attention to balanced nutrition during infancy and early childhood, and advocate breastfeeding; reduce the intake of excessive high protein and low fiber diet during childhood development; do not consume large amounts of fat and animal protein during adolescence, and strengthen physical exercise; control the total calorie intake after menopause to avoid obesity. Usually develop a diet without excessive intake of meat, fried eggs, butter, cheese and sweets, eat less pickled, smoked, fried and baked foods, and increase the consumption of fresh vegetables, fruits, vitamins, carotenoids, olive oil, fish and bean products. 4.Actively treat breast diseases. 5.Do not use exogenous estrogen indiscriminately. 6.Do not drink alcohol excessively for a long time. 7. Carry out pharmacological prevention among people with high risk of breast cancer. The National Cancer Center is responsible for conducting an exploratory study on the prevention of breast cancer with drugs such as triamcinolone and raloxifene. It is recommended that women learn some scientific knowledge about breast diseases, master breast self-examination methods, develop the habit of regular breast self-examination, and actively participate in breast cancer screening to prevent the disease before it happens.