The 5-year survival rate of patients with moderately differentiated stage Ⅰa lung adenocarcinoma is about 84.4%, and the specific prognosis should be judged according to the general condition of the patients and the effect of treatment. Stage Ⅰa lung adenocarcinoma is divided into Ⅰa1, Ⅰa2 and Ⅰa3 according to the size of the tumor, and the difference is that the maximum diameter of each stage is different, the maximum diameter of Ⅰa1 tumor is ≤1cm, the maximum diameter of Ⅰa2 tumor is in the range of 1-2cm, and the maximum diameter of Ⅰa3 tumor is >2cm. according to the survey, the 5-year survival rate of Ⅰa1, Ⅰa2, and Ⅰa3 are 96.9%, 88.9% and 67.7%, respectively, 67.7%. If patients are diagnosed with moderately differentiated stage Ia lung adenocarcinoma, they should go to the hospital as early as possible for surgical treatment, supplemented with lymph node dissection. Generally speaking, the surgery can completely remove the lesion, and the probability of recurrence and metastasis is small, so the prognosis is generally good, and some patients can even survive for a long time. Patients should undergo regular postoperative checkups and maintain a good attitude in order to prolong survival.