Lung adenocarcinoma, in the early stage, has no obvious symptoms, and in the middle and late stage, it may have symptoms such as cough, hemoptysis, chest pain and so on. The specific symptoms are related to the size and location of the tumor as well as individual differences of patients. 1. Cough: Most of the patients with lung adenocarcinoma usually have unexplained cough as the first symptom, which is usually irritating dry cough with paroxysm. It can be accompanied by shortness of breath, wheezing, and in serious cases, dyspnea. 2. Hemoptysis: Some patients with adenocarcinoma of the lungs may be found with hemoptysis, which is usually blood in sputum and a small amount of hemoptysis in bright red color. 3. Chest pain: if the tumor stimulates the pleura, chest pain may appear, which is dull pain or hidden pain. In addition to the above symptoms, patients with thymic cancer may also have Hoarseness, superior vena cava compression syndrome such as jugular vein filling, and systemic manifestations such as emaciation, fatigue, loss of appetite and cachexia can be seen in late stage. If the above symptoms occur at the same time and persistently cannot be relieved, it is necessary to be alerted to lung adenocarcinoma, and one should consult the doctor in time to clarify the cause of the disease, so as to avoid delaying the condition.