Hidden pain under the left rib, most consider trauma, heart disease, intercostal neuralgia, pleurisy, lung disease and so on. 1. Trauma: there is a clear history of trauma, resulting in local soft tissue or rib fractures, manifested as chest pain, chest tightness, coughing or deep breathing pain aggravated, local skin lesions or bruises. 2. Heart disease: such as angina pectoris, caused by narrowing or occlusion of coronary artery lumen, manifested as chest tightness and chest pain. 3. Intercostal neuralgia: pain distributed along the intercostal nerves, mostly band-like distribution, stabbing or burning pain, coughing, deep breathing pain aggravated. 4. Pleurisy: inflammation occurring in the pleural cavity, with fever, cough, chest pain, dyspnea and other symptoms. 5. Lung diseases: such as lung cancer, early cough is the most common, manifested as paroxysmal irritating dry cough, if the tumor invades the adjacent tissues, it may manifest as vague pain or dull pain in chest, and the pain may be aggravated when coughing. There are other causes of left subcostal pain, and it is recommended that patients go to the hospital in time to avoid delaying the condition.