There are various causes of chest pain late at night, the most common cases are as follows: 1. The pain may be caused by angina pectoris, which is usually associated with coronary heart disease. Insufficient blood flow due to narrowing of the arteries supplying blood to the heart muscle, combined with insufficient oxygen required for work, leads to localized ischemic pain. The pain lasts for 3-5 minutes and sometimes resolves on its own.2. Pain caused by acid reflux. When acid refluxes into the esophagus, it irritates the esophageal mucosa, causing pain and difficulty swallowing.3. Heart failure. When a person lies down the blood is redistributed and the amount of blood returning to the heart increases. The heart will need more blood than when standing, leading to heart failure, which manifests as shortness of breath, chest tightness and chest pain. If a patient experiences chest pain in the middle of the night or has such symptoms for a long time, promptly go to a local hospital for relevant tests to clarify the diagnosis and provide timely treatment.