Blood test for hepatocellular carcinoma mainly depends on AFP, but also some other indicators, such as AFP heteroplasm, γ-glutamyl transferase isozyme II (GGT2), abnormal prothrombin (APT), etc. Among them, AFP is the specific marker and main indicator of hepatocellular carcinoma. 1. It is not only an important index for diagnosing liver cancer, but also an important basis for judging whether there is recurrence of tumor after resection. The normal value of methemoglobin is <20μg/L. If methemoglobin is >400μg/L and persistently elevated, and pregnancy, active liver disease and germinal gland embryonic tumor can be excluded, the diagnosis of hepatocellular carcinoma can be considered; 2. Other indicators: some patients with hepatocellular carcinoma have completely normal methemoglobin, then methemoglobin heteroglobin should be tested, and if methemoglobin heteroglobin is positive, it also helps to judge. Some other markers, such as γ-glutamyltransferase isoenzyme II and abnormal prothrombin, also help in the diagnosis and differential diagnosis of hepatocellular carcinoma when methemoglobin is negative, so multiple markers can be combined to improve the diagnosis rate. Along with the above liver cancer marker tests, some imaging examinations, such as ultrasound imaging, CT examination, MRI examination, liver angiography, etc., are also recommended. Cancer nodes can also be punctured with a fine needle under ultrasound or CT guidance and histological examination can be performed. In case of tumors on the liver surface, laparoscopy can also be used. It is recommended to combine multiple examination modalities to improve the diagnosis rate.