Carcinoembryonic antigen 15ng/ml belongs to the obvious elevation of tumor indicators, which is more serious if it is caused by cancerous diseases, while it is not serious if it is elevated due to benign diseases. Carcinoembryonic antigen (CEA) is a commonly used clinical tumor indicator, with normal value less than 5ng/ml, mainly used in the clinical monitoring of colorectal, gastric, pancreatic, hepatocellular, lung, breast and medullary thyroid cancers, and also in choriocarcinomas, bone, prostate and ovarian cancers, but has no early diagnostic value. In addition, mild increase in carcinoembryonic antigen is also seen in certain benign gastrointestinal diseases such as intestinal obstruction, biliary obstruction, pancreatitis, cirrhosis of the liver, colon polyps, ulcerative colitis, as well as in smokers and the elderly. It is recommended to further improve the relevant examination to clarify the cause of the disease and take appropriate treatment to avoid delaying the condition.