Left anterior chest and left back pain may be related to angina pectoris, intercostal neuralgia, respiratory diseases and so on. 1. Angina: left anterior chest and left back pain should first consider angina pectoris, angina pectoris is characterized by sudden onset of crushing pain or discomfort in the posterior part of the sternum or the precordial region extending to the left side of the chest, which may be radiated to the left posterior back, or the back of the left shoulder, or the left arm. It is often accompanied by palpitations (rapid heartbeat, often accompanied by panic), chest tightness and shortness of breath. 2. Intercostal neuralgia: refers to the pain syndrome in the area innervated by the intercostal nerves, mostly caused by neuritis or thoracic vertebrae compressing the nerves. It is often manifested as pain in the intercostal area, distributed in a band, radiating pain from the back to the chest, which can be exacerbated episodically and worsened when coughing, sneezing or deep inhalation, and is manifested as pain in the left anterior chest and the left posterior back. 3. Respiratory diseases: such as pneumonia or lung tumor, the lesion often involves the pleura, chest pain symptoms, such as pain can be radiated to the back of the shoulder when the pain is severe, manifested as left anterior chest and left back pain. It is often accompanied by cough, fever, fatigue and other symptoms. Left anterior chest and left back pain may also have other causes, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy.