It is well known that AFP is a specific marker of liver cancer and is currently used as a tumor indicator for the diagnosis and screening of primary liver cancer. Generally, patients with primary liver cancer will have a substantial increase in AFP. For further study and understanding of the clinical significance of elevated AFP: AFP is a major protein in embryonic serum, a tumor-associated antigen, mainly synthesized by the fetal liver, which declines sharply after birth and drops to normal levels (20ng/ml) in newborns within a few months to a year after birth, as a single peptide chain with a molecular weight of 65000-70,000. The main reasons for elevated AFP are 1. In adults, elevated alpha-fetoprotein is seen in the serum of about 80% of patients with hepatocellular carcinoma, and the rate of positive alpha-fetoprotein in germ cell tumors is 50%. Therefore, elevated AFP generally implies the occurrence of hepatocellular carcinoma. The amount of alpha-fetoprotein in normal human serum is usually less than 20ng/ml, but when hepatocellular carcinoma occurs, the function of producing this protein is restored, so elevated alpha-fetoprotein should be considered as a possibility of hepatocellular carcinoma. 2.Pregnant women and newborns may also have a momentary elevation of AFP because AFP is a normal plasma protein component of the fetus and is the main protein of the early embryo. AFP in pregnant women is significantly elevated, generally in the third month after pregnancy, AFP rises significantly, and by July-August the amount of AFP in maternal blood of pregnant women reaches its peak and is relatively stable, but it is still lower than 400ng/ ml, and gradually return to normal level about 3 weeks after delivery. 3.There is mild or moderate elevation of AFP in the active stage of chronic hepatitis, generally in the range of 50-300ng/ml, which differs from hepatocellular carcinoma in that the elevation is low and generally does not increase continuously, and it decreases to normal after treatment. 4.AFP can be measured in 30% of neonatal hepatitis, the incidence increases with the severity of the disease, and most of them are significantly higher. 5, liver injury, congestive hepatomegaly, capillary dilation, testicular or ovarian embryonal tumors (such as seminoma, malignant teratoma, ovarian cancer, etc.) also often have elevated alpha-fetoprotein. Thus, methemoglobin is a serum marker for the diagnosis of early hepatocellular carcinoma. However, the diagnosis of hepatocellular carcinoma needs to be combined with the results of multiple examinations, and a single initial screening test of elevated AFP is not equivalent to the diagnosis of hepatocellular carcinoma. Therefore, when we encounter such a situation, we should not immediately judge ourselves as having liver cancer, but at the same time, we should have a certain sense of worry and actively cooperate with doctors for various examinations, so as to be responsible for our own health.