The causes of chest pain caused by sleeping pressure are more reasons, mainly including improper sleeping posture, overwork, intercostal neuritis, heart disease, breast hyperplasia and so on. 1. Improper sleeping position: If you sleep in a prone position, the effect of gravity, the chest wall muscles and soft tissues for a long time by the pressure, easy to cause damage, thus triggering chest pain. 2. Overwork: If you stay up late for a long time or play intense sports, it may cause chest joints and muscles to be damaged, and if you accidentally press on the damaged part when sleeping, it will easily cause chest pain. 3. Intercostal neuritis: Some non-specific infections, such as intercostal neuritis, may be triggered by improper sleeping position, thus causing chest pain. 4. Heart disease: If there is insufficient blood supply to the heart, angina pectoris, coronary heart disease, etc., the chest pain may be caused by sleeping in an improper posture, which presses the heart. 5. Breast Hyperplasia: If there is cystic hyperplasia of the breast, it may cause chest pain if it is accidentally pressed to the part of breast hyperplasia when sleeping. If there is a chest pain when sleeping, you should go to the hospital in time for examination to clarify the cause of chest pain and carry out targeted treatment as soon as possible.