The early stage of lung cancer lacks specific symptoms, but some individuals have cough, hemoptysis, chest and back pain, wheezing and fever of unknown origin. As we know, lung cancer is a malignant tumor in the lungs of respiratory organs, so its manifestation is closely related to the location of its occurrence. Generally speaking, lung cancer is divided into central type lung cancer and peripheral type lung cancer. In general, central type lung cancer presents itself a little earlier, because it attacks in the bronchial tubes and presents cough, sputum and blood or chest discomfort earlier. Peripheral type lung cancer lacks symptoms in early stage, but once the tumor involves the pleura, it will show chest pain, and if it develops further, it will show pleural lesions and lead to pleural effusion. In the examination of lung cancer, emphasis is placed on high-risk groups, the first being heavy smokers, the second being family history and immediate family members with a history of malignant tumors, especially lung cancer. If there is an irritating dry cough and blood in the sputum, this should be checked at the hospital. Other chest pain or chest discomfort should also be checked regularly if you are a heavy smoker or a high-risk group. Early detection requires regular physical examination, including chest fluoroscopy, blood tests and other appropriate tests. This can detect early lung cancer and provide timely treatment. There are three levels of early detection. Generally speaking, in order to detect lung cancer at an early stage, a country has to screen the high-risk groups, that is, the areas with high incidence of lung cancer, and the people with high incidence of lung cancer, which is the national action. First of all, to be a healthy citizen should insist on annual health checkups, which is the most important. It is very important to do annual health checkups, but also to focus on the chest frontal and lateral medical examinations, once some netizens said I also had a medical checkup, just do chest X-ray, but also not. Second, only the frontal chest film, also not. Should also do the standard chest X-ray front and side, the conditions of the region, the conditions of the unit, the conditions of the population, but also advocate doing some primary spiral CT, the cost and chest X-ray is about the same, bear the radiation is also very low. Third, heavy smokers, more than 20 cigarettes a day, more than 20 years, these smokers advocate annual physical examinations, the conditions of the population, advocate low-dose CT, there are many places to low-dose CT into the normal physical examination. Can also do tumor marker association test. In conclusion, healthy people, smokers and people with respiratory manifestations should be alert to the onset of lung cancer and should pay attention to health checkups and timely checkups in regular hospitals. Early stage lung cancer can achieve a high cure rate, with a 5-year survival rate of even 100%.