Objective To discuss clinical diagnostic value of combined detection multiple tumor marker contents in the lung cancer.Methods Selected 35 cases of lung cancer and another 35 cases of benign lung diseases as a control group admitted in our hospital from February 2007 to December 2010.Detected the levels of CEA、serum CA19-9、NSE and CYFRA21-1.Results The levels of single tumor markers in lung cancer group showed no significant difference from benign lung diseases group(P0.05),various levels of tumor markers for diagnosis of lung cancer had a sensitivity of 50.04%,specificity of 93.42%,accuracy of 72.94%.Conclusion Combined detection of 4 tumor markers for the diagnosis of lung cancer is great significance,is better than individual testing,provides more powerful evidence for diagnosis and differential diagnosis of lung cancer.