Pain in the breast without nodules may be due to breast enlargement, trauma or mastitis. 1. Mammal hyperplasia: Mammal hyperplasia will lead to painful symptoms in the breast, usually the pain will be obvious when a woman is menstruating, and the pain will be alleviated after the menstruation period. When the disease is mild, there is usually no obvious breast nodules. However, as the disease progresses, nodules may appear and nipple discharge may occur. 2. Trauma: When the breasts are squeezed or bumped, the soft tissues in the breast area will be bruised, resulting in localized skin redness, swelling and pain, and the pain will increase when pressed. 3. Mastitis: Mastitis can cause pain, heat, redness, swelling and other symptoms in the breast area, in the acute stage of inflammation, the patient will have a higher body temperature, breast pain is serious, accompanied by breast overflow, some patients will be ulcerated, pus outflow. At the same time, some female physiological conditions can also appear breast swelling and pain, mostly concentrated in the period before and after the onset of menstruation, there will be breast swelling and pain; at the same time, puberty female breasts are in the stage of development may also be the case of breast swelling and pain. In addition, diseases of the breast skin, as well as diseases of the lungs, pleura, heart, etc. can also show pain around the breast, and should be identified. There are many other causes of breast pain without nodules, so it is recommended to consult a doctor to determine the cause and treatment plan.