The left side of the chest pain should be treated according to the cause, common causes include pleurisy, angina, cardiac neurosis, etc., the treatment includes medication, psychotherapy, etc., the drug should be used in strict accordance with the doctor’s instructions. 1. Pleurisy: inflammatory disease of the pleura, often secondary to the lungs, with clinical manifestations such as vague pain and stabbing pain in the chest, shortness of breath, fever, etc. The principle of treatment is to relieve the cause of the disease, alleviate the pain and relieve the angina. The principle of treatment is to relieve the cause of the disease and relieve the pain. For mild and moderate pain, non-steroidal anti-inflammatory drugs such as ibuprofen and aspirin can be used; for more severe pain, it can be combined with narcotic analgesics such as codeine. 2. Angina pectoris: mostly occurs during labor or emotional excitement, manifested as a crushing, constriction-like pain behind the sternum or in front of the left chest, often radiating to the left shoulder and the inner side of the left arm. Some patients only feel slight discomfort in the precordial area. The duration is usually 3~5 minutes, which can be quickly relieved by resting or taking nitroglycerin. 3. Cardiac neurosis: It is more common in middle-aged women, especially menopausal women. The pain is most common in the left anterior breast or inframammary region. The nature of the pain varies, or persistent vague pain, but most of them are transient, and there are no episodes of chest pain during physical activities. Treatment is based on psychotherapy, with medication: anti-anxiety drugs such as alprazolam, receptor blockers such as metoprolol. Hidden pain on the left side of the chest may also be seen in other diseases, such as lung cancer, etc., should be timely hospital consultation, improve the relevant examination, diagnosis and treatment by a professional doctor to synthesize the clinical manifestations, auxiliary examination, etc., should be avoided to blindly self-medication, in order to avoid delaying the condition.