Stage lA2 lung adenocarcinoma is T1bN0M0 IA2 stage in TNM staging of lung adenocarcinoma. lA2 stage lung adenocarcinoma generally refers to early stage of lung adenocarcinoma. Lung adenocarcinoma of stage lA2 belongs to early stage. in TNM staging, T stage refers to the size of primary tumor, N stage refers to lymph node metastasis, and M refers to distant metastasis. stage IA2 is T1bN0M0, which refers to the maximum diameter of the tumor >1cm, ≤2cm, without lymph node and distant metastasis. Patients with stage IA2 lung adenocarcinoma may have no obvious symptoms, or the symptoms may include cough, low fever, chest pain and so on. Generally patients’ cough will show different degrees of sputum, and some patients may have the phenomenon of blood in sputum. Generally speaking, the examination of stage lA2 lung cancer is determined by chest CT examination, B-mode ultrasound examination, MRI examination, bone scanning examination, PET-CT examination, etc. Through these examinations, doctors can clearly understand the degree of the patient’s condition in order to formulate a suitable treatment plan for the patient. Surgery is generally preferred for the treatment of stage lA2 lung cancer, and postoperative adjuvant chemotherapy may not be necessary. If the patient is unable to undergo surgery due to age or physical condition, he/she can choose stereotactic radiotherapy for radical treatment, which can achieve a better prognosis. Early stage lung adenocarcinoma suggests patients to actively cooperate with doctors to increase the chance of cure.