A cough pain under the left chest may be related to tuberculosis, pleurisy, pneumothorax, etc., and should be emphasized and actively treated. 1. Tuberculosis: tuberculosis foci are close to the pleura, pulling on the pleura when coughing, causing pain under the chest, tuberculosis foci invade the pleura position, causing tuberculosis pleurisy, which can also lead to the manifestation of chest pain, especially when coughing violently chest pain symptoms will be aggravated. 2. Pleurisy: when inflammation stimulates the left chest, it will cause left chest pleurisy, and the local pleura rubs when coughing, which is often manifested as chest pain, and if the pain is obvious, it indicates that the symptoms of pleurisy are gradually aggravating. 3. Pneumothorax: If pneumothorax occurs, pleural adhesions pulling and tearing, stimulating the local pleura, there will be coughing, and violent coughing will cause chest pain. Pain in the lower left chest, should promptly seek medical attention, under the guidance of the doctor to identify the cause of the disease, symptomatic treatment.