Abstract: The current international TNM staging for lung cancer plays an important role in the development of treatment strategies and prognosis judgment of lung cancer. The prognosis differs among patients in the same stages，probably due to tumor micrometastases. The tumor micrometastases can be detected by molecular biology techniques and molecular markers. On the basis of TNM classification，the molecular staging of lung cancer can be developed to remedy the deficiency of TNM staging system. With the molecular staging of lung cancer，the development of standardized treatment program is of importance to reduce tumor recurrence and metastases, as well as improve prognosis.