The yellow milky milk extruded from the chest may be normal milk, or it may be caused by diseases such as intraductal papilloma of the breast and breast cancer, which are abnormal phenomena. 1. Normal milk: breastfeeding women will secrete colostrum within 7 days after the delivery of the fetus, colostrum is thicker and yellowish in color, so it may be normal to have yellow milky milk coming out of the breast at this time. 2. Intraductal papilloma of breast: this disease may be caused by pregnancy, drugs and other factors, papilloma stimulation of breast tissue may appear yellow milk-like nipple discharge. 3. Breast cancer: some patients with breast cancer may have nipple discharge, and the breast may secrete yellow milky fluid. Chest extrusion of yellow milk-like milk can be timely consultation, under the guidance of physicians to identify the cause of the disease.