Pain under the collarbone above the breast can be caused by breast disease, lung disease, heart disease, rib disease and other factors, patients should consult a doctor in time to clarify the cause of the disease. 1. Breast disease: a common breast disease that can cause pain under the collarbone above the breast is cystic hyperplasia of the breast, the pain is cyclical, mostly in the imminent menstruation is more painful, this group of people should go to the hospital regularly for review. 2. Lung disease: the most common lung disease that can cause pain below the clavicle above the breast is pneumothorax, such patients have lifted weights or have underlying lung disease before the pain occurs, the pain is pinprick-like, and chest drainage can be carried out if there is a large amount of gas. 3. Heart disease: for the elderly with high blood pressure and high blood fat, if they have pain in the lower part of the clavicle above the breast, it should be considered to be caused by coronary heart disease, and the patients should be treated with drugs such as nitroglycerin and heparin. 4. Rib lesions: rib lesions that can cause pain below the sternum and above the breast are costochondritis, costal neuralgia, etc., and their pain shows a band-like distribution. The pain is distributed in bands. Therefore, it is necessary to consult a doctor in time to clarify the cause of the disease and then carry out the corresponding treatment.