Chest pain is seen in many diseases and can be diagnosed as well as differentially diagnosed by electrocardiography and chest CT. Common diseases include the following: First, myocardial ischemia, where the patient has anterior heart pain as well as chest tightness and palpitations, and an electrocardiogram may reveal significant ST-segment changes. Second, diseases such as pulmonary embolism or aortic coarctation, which need to be further identified by performing the appropriate vascular examination. Third, chest pain associated with lung tissue infection, accompanied by fever and cough and sputum, and CT examination may reveal patchy images in the lungs. Patients with pleural effusion will show pins and needles pain in the chest in the early stage, and as the disease progresses, effusion will appear, and the patient will also have chest tightness and even dyspnea, and chest X-ray can confirm the diagnosis. Fourthly, malignant tumor of lung tissue, mainly lung cancer, with the evolution of the disease, it is easy to involve the wall pleura and even pleural metastasis, which is manifested as chest pain, and also loss of appetite and weight loss.