The normal liver receives a dual blood supply from the hepatic artery and portal vein, with the hepatic artery supplying 20-25% of the blood and 50% of the oxygen, and the portal vein supplying 75-80% of the blood and 50% of the oxygen. The terminal branches of both the hepatic artery and portal vein end at the hepatic sinusoids, and there is still an extensive anastomosis between them, so when either of the artery and portal vein is blocked, the blood flow to the other side will increase compensatorily. When either artery or portal vein is blocked, blood flow to the other increases compensatively. The liver tissue supplied with blood does not become necrotic. Almost all (90-95%) of the blood supply in primary and metastatic hepatocellular carcinoma comes from the hepatic artery and rarely from the portal vein. Therefore, hepatic artery embolization can block or reduce the main blood supply to the tumor, causing necrosis, shrinkage or even disappearance of the tumor, and normal liver tissues will not be seriously affected. Therefore, the commonly used clinical chemoembolization is the organic combination of anti-cancer drugs and embolic agents injected into the hepatic artery, which can not only embolize the peripheral blood vessels of tumor tissues and block the blood supply, but also slowly release the chemotherapeutic drugs to kill tumor cells. This is the theoretical basis of hepatic artery embolization for the treatment of hepatocellular carcinoma. The method can be used as the main treatment for primary or metastatic hepatocellular carcinoma that cannot be removed surgically for various reasons, or for all types of hepatocellular carcinoma that patients are unwilling to operate. 2. Contraindications (1) Severely impaired liver function, total bilirubin >50Umol/L, ALT >120U, massive ascites or severe cirrhosis, liver function of Child C; (2) Complete obstruction of the main trunk of the portal vein, with little formation of collateral vessels, embolization is not done as far as possible; (3) Prothrombin time is more than 2 times of normal. (4) cancer occupying 70% or more of the whole liver (if liver function is basically normal, embolization can be performed with a small amount of iodine oil in stages); (5) severe portal hypertension, severe varices of the fundus and esophageal veins, with the risk of rupture and bleeding, embolization should be performed with caution; (6) severe hepatic artery-portal fistula or hepatic artery-hepatic vein fistula, the fistula opening cannot be effectively sealed, embolization should not be performed. (7) Leukocytes <3×109/L; (8) Extensive metastases in the whole body; (9) Systemic failure.