Hidden pain in the left chest under the ribs may be some physiological phenomena, but also may be the manifestation of certain diseases, such as chest wall diseases, coronary heart disease, digestive system diseases, etc., should be timely consultation to find out the cause of the disease. 1. Physiological factors: when doing strenuous exercise for a long time, it can also lead to left chest pain under the ribs, which usually can be relieved after resting, without special treatment. 2. Pathologic factors (1) Chest wall diseases: such as rib chondritis and intercostal neuralgia caused by various reasons, it will cause the symptom of rib pain under the left chest, and the symptoms can be aggravated by lifting up the ribs when inhaling deeply. (2) Coronary heart disease: angina pectoris caused by coronary heart disease can also lead to symptoms of pain around the ribs on the left side of the chest. This is because the coronary arteries are narrowed or even occluded, which will trigger myocardial ischemia when myocardial oxygen consumption increases, and myocardial ischemia will be manifested as the symptom of pain in the left side of the chest. (3) Digestive system diseases: including gastric ulcer, duodenal bulb ulcer, can also be manifested as the left side of the chest under the symptoms of pain around the ribs, and this symptom and diet have obvious correlation. If physiological causes are ruled out, you should consult a doctor to clarify the cause of the disease and conduct appropriate examinations if necessary.