Staging of lung adenocarcinoma cannot be clarified solely on the basis of the degree of cell differentiation. The stage is based on the primary tumor, lymph node metastasis and distant metastasis. Lung adenocarcinoma is one of the pathological types of lung cancer, which is more common in women and can be caused by smoking, heredity, environment and other factors. Intermediate differentiation represents the degree of differentiation of cancer cells, i.e., it is obtained from pathological examination of cancer tissues, and can be divided into undifferentiated, moderately differentiated, and highly differentiated, and generally the lower the degree of differentiation, the higher the degree of malignancy. In general, the lower the differentiation degree, the higher the malignancy. Among them, the middle differentiation represents the general malignancy and general prognosis of the tumor. The staging is based on the primary tumor, lymph node metastasis and distant metastasis, and can be divided into four stages. The later the staging, the more complicated the condition and the worse the prognosis, and the staging can be used to guide the adoption of appropriate treatment methods and judge the prognosis.