Pain under the right side of the chest is usually seen in pulmonary diseases and diseases of the hepatobiliary system. I. Pulmonary diseases: seen in the case of pneumonia or pleurisy, pneumonia involves the pleura and can cause chest pain associated with breathing, often manifested as chest pain that worsens when the patient inhales deeply, coughs and turns the body position, and decreases or disappears when the patient holds his breath. It is recommended to do chest X-ray and lung CT examination to clarify the diagnosis. Second, hepatobiliary system diseases: when the patient has gallbladder inflammation, gallbladder stones or liver abscess, liver cancer and other diseases, pain can appear in the lower right chest or right upper abdomen position, accompanied by nausea, vomiting, anorexia, jaundice and other symptoms, it is recommended to do liver, gallbladder and spleen ultrasound and liver function examination to make a clear diagnosis.