Lung cancer is a kind of malignant tumor that seriously endangers human health, and the symptoms are different at different periods. The early symptoms of lung cancer are not obvious, while the main symptoms in the middle stage of lung cancer include cough, hemoptysis, chest pain, chest tightness and so on. In the middle stage of lung cancer, cough is mainly dry cough with no sputum or a small amount of sputum with blood in it, hemoptysis, intermittent repeated small amount of sputum and blood, occasionally hemoptysis is fresh blood, the duration is not the same, some of them are months long; chest pain is the pain caused by lung cancer invading the nerves of pleura, mainly appearing as pleural effusion, dull pain in chest, tumor compressing the sternum, ribs or intercostal nerve. The pain is caused by the tumor pressing on the sternum, ribs or intercostal nerve; shortness of breath is caused by the middle stage of lung cancer, the tumor presses and obstructs the narrowing of trachea, resulting in tracheal dyspnea; widespread spread of lung cancer causes chest tightness and difficulty in breathing; hoarseness is caused by the tumor invading the left laryngeal nerve of mediastinum, and the compression will lead to hoarseness of voice. Lung cancer needs to be diagnosed by chest CT, bronchoscopy, PET-CT and other diagnostic methods to determine the type of lung cancer. Clinicopathological staging is performed. Different types of lung cancer have different treatment plans, and the treatment methods include a combination of surgery, chemotherapy, radiotherapy and other comprehensive treatments. In short, lung cancer needs to be diagnosed and treated as early as possible. The treatment method is based on the disease, mainly surgery, combined with chemotherapy, radiotherapy, targeted and immunotherapy.