The common causes of red dots on breasts are contact dermatitis, breast eczema, spider nevus and other causes, and you should consult a doctor in time to find out the cause of the disease. 1. Contact dermatitis: the skin of the breast is exposed to certain exogenous substances, an inflammatory reaction occurs, which causes the phenomenon of red spots on the breast, usually accompanied by redness, swelling, pimples and itching symptoms. 2. Breast eczema: Inflammation caused by a variety of factors, usually manifested as eczema, some people with mild symptoms will appear red spots, red spots phenomenon. 3. Spider nevus: it is a kind of vascular damage, one of the benign and common diseases, usually occurring in the breast, face, neck and other parts. The symptoms of red dots on the breast, it is recommended to go to the hospital in time for relevant examination, identify the cause of the disease, and follow the doctor’s instructions for treatment.