There are two types of tumor markers for lung cancer, as follows: 1) tumor markers used for the diagnosis of non-small cell lung cancer, including tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), squamous carcinoma antigen (SCC), and cytokeratin 19 fragment (CYFRA21-1); 2) tumor markers used for the diagnosis of small cell lung cancer, including neurospecific enolase (NSE), bell toad peptide ( BN), creatine phosphate isoenzyme (CPK-BB), gastrin (GRPC), etc. There is no reliable serum tumor marker with high specificity for the diagnosis of lung cancer, but when the above tumor markers are tested in combination, they have some reference value for the diagnosis of lung cancer and monitoring of the disease.