The focus of hepatic artery chemoembolization is to embolize the tumor blood supply artery. The blood supply artery of small hepatocellular carcinoma is mostly thin and distal to the 3rd and 4th level branches of the hepatic artery, with long and tortuous travel in the liver. Even if the 5F catheter is inserted into the straight tumor-supplying artery, it may damage the intima and cause stenosis or occlusion of the hepatic artery, which is unfavorable to the later interventional treatment. Because the distal end of the microcatheter is 2.7F (0.9mm in diameter), it can be inserted into the finer hepatocellular carcinoma blood supply artery. The use of microcatheter can maximize the insertion of small hepatocellular carcinoma blood supply arteries for precise embolization treatment, which promotes the necrosis of cancer tissues, which is especially important for the treatment of small hepatocellular carcinoma, which still has considerable portal vein blood supply. Push in iodine milk under certain pressure can achieve dense embolization of small hepatocellular carcinoma blood supply artery, so that iodine milk can overflow into small branches of portal vein through the traffic branches of terminal small artery and anterior small artery level and portal vein to achieve the purpose of double embolization of tumor artery and portal vein, thus obviously improving the treatment effect.