The survival period of lung cancer stage II after surgery depends on the postoperative adjuvant treatment. Stage II lung cancer is a relatively early stage of cancer, including stage IIA and stage IIB. Stage IIA patients generally do not need adjuvant chemotherapy after surgery, and on average, half of them can live beyond five years. Stage IIB patients generally need adjuvant chemotherapy after surgery, and 30%-40% of patients can survive up to five years. Of course, if patients do not respect medical advice and are not given adjuvant therapy after surgery, the recurrence rate is higher and fewer patients will survive for five years. In addition, if the patient is in poor health and cannot tolerate post-operative adjuvant therapy, the survival period will also be discounted. In conclusion, stage II lung cancer is an early stage cancer, and half of the patients can survive up to five years after surgery, and the vast majority of patients are above two years. The survival of patients is affected by the post-operative adjuvant treatment and the patients’ own physical condition, so it cannot be generalized.