There are many indicators of colon cancer blood test, if we want to clarify the diagnosis of colon cancer, we usually need to check the blood routine and tumor indicators, the blood routine is mainly to understand whether there is anemia, such as whether red blood cell, hemoglobin or red blood cell pressure product is reduced, the tumor indicators mainly include carcinoembryonic antigen or CEA, also need to check AFP, CA199, CA125 and so on. Carcinoembryonic antigen is the sensitivity index of colon cancer, if the carcinoembryonic antigen is elevated the possibility of colon cancer is high, but normal carcinoembryonic antigen does not exclude that the patient does not have colon cancer, if AFP or CA199 is high it means that colon cancer may have intra-abdominal implantation metastasis or distant metastasis, etc. If the patient needs surgery, there are more items to check the blood, including the infection immunity routine, that is, hepatitis B, syphilis, AIDS, etc., and also need to check the coagulation to understand whether the patient can tolerate the surgery.