According to the TNM staging of lung cancer, the diameter of lung cancer lesion is 1.3 centimeters, suggesting that the disease is in T1b stage. If there is no lymph node or distant organ metastasis, the patient is in IA2 stage, which is early clinical stage. If combined with lymph node or distant organ metastasis, the clinical stage should be judged according to the metastasis of the lesion. Lung cancer is a malignant tumor disease originated from bronchial epithelial cells. It is currently believed that the clinical staging of lung cancer is related to tumor size (T), lymph node metastasis (N) and distant metastasis (M). Lung cancer lesions of 1.3 centimeters are between 2-3 cm, and the tissue of the lesion is in T1b stage. However, clinical staging needs to be judged comprehensively according to lymph node and distant organ metastasis; if there is no lymph node and distant organ metastasis, it is in early clinical stage. If there are lymph nodes and/or distant organs metastasis, the disease may be in the middle or late clinical stage. Clinical staging of lung cancer patients should not only focus on the size of tumor lesions, and it is suggested that patients should pay close attention to the development of the disease, consult doctors in time, and follow the doctor’s instructions to avoid aggravating the patient’s condition. Besides, patients should avoid smoking and drinking alcohol and develop healthy living habits.