Breast pain can be caused by breast trauma, mastitis or breast hyperplasia. 1. Breast trauma: When the breast area is damaged by the outside world, swelling and pain may occur. Pressing on the breast will increase the irritation to the area, causing the patient to experience pain when the breast is pressed. 2. Mastitis: Mastitis can be induced by bacterial growth in the breast area, and repeated stimulation by inflammation can lead to pain when the patient’s breasts are pressed, accompanied by redness and obvious enlargement. 3. Mammal hyperplasia: When the metabolism of endocrine hormones is imbalanced, it can produce continuous stimulation of the mammary glands and induce mammary gland hyperplasia. With this disease, lumps may appear in the breast area, and when the breast is pressed, it will lead to lumps and cause pain by pressing on the peripheral nerves. Breast pain when pressed can also be caused by fibroids, cardiothoracic diseases, herpes zoster, breast cancer, etc. Patients should go to the hospital in time to receive treatment.