Vague pain under the right breast is considered to be related to right side lung disease, chest trauma, breast disease and other causes. 1. Right lung disease: If lung infection, tumor, tuberculosis and other diseases involve the pleura, it can lead to a vague sensation under the right breast. In addition, it can be accompanied by symptoms such as cough and fever. 2. Chest trauma: when the right side of the chest suffers from trauma, it may lead to contusion of the soft tissues of the right breast, which may cause local redness, swelling, heat and pain. 3. Breast diseases: If there are lesions in the right breast of the patient, such as breast cystic hyperplasia, which is generally a benign hyperplasia of the breast parenchyma, it is usually caused by hormone metabolism disorders (e.g., imbalance of estrogen/progesterone ratio), which results in an imbalance of over-expansion of the breast parenchyma and under-regeneration, thus leading to the occurrence of breast cystic hyperplasia. It causes the breasts to show symptoms of swelling and pain. At the same time, a lump is palpable on touching the breast. At the same time, skin diseases, intercostal nerve diseases, rib diseases, pleural diseases may show the manifestation of hidden pain under the right breast. There are many reasons that lead to hidden pain under the right breast, if there is hidden pain under the right breast, it is recommended to go to the hospital in time for examination, clear diagnosis, and treatment under the guidance of the doctor, so as not to delay the condition.