Breast secretion may be physiological phenomenon or pathological condition. 1. Physiological phenomenon: when a breastfeeding woman is weaned for a short period of time, the milk has not completely stopped being secreted, or there is residual milk in the breast, there will be a small amount of milk secretion, especially when the breast is squeezed with the hand, there will be milk secretion; it is a normal phenomenon, and usually does not need to be dealt with. 2. Pathologic conditions: (1) With pituitary microadenoma, as the tumor can secrete prolactin and promote milk secretion, secretion may also be seen from both breasts, and may be accompanied by symptoms such as dizziness, headache, or loss of vision. (2) If women who are not breastfeeding have breast discharge, they can also consider whether there are breast tumors or not. If there are local lumps, pain or local skin changes, they need to consider whether there are intraductal papilloma or breast cancer. (3) Cystic hyperplasia of the breast: in addition to periodic breast pain, patients may also have nipple discharge, which is colorless, transparent or yellowish. When there is breast discharge, especially in non-lactation period, it is necessary to pay attention to it and go to the hospital in time, and the professional doctor will give relevant examination, such as CT of pituitary gland or molybdenum target or CT examination of breast, so as to exclude relevant tumors in time.