Portal vein and body vein are two different venous circulation systems. Portal vein bypass is a surgical treatment for complications of portal hypertension, in which a collateral circulation is surgically established between the portal vein and the inferior vena cava to reduce the portal vein pressure by shunting the higher pressure portal vein into the inferior vena cava. Most of the portal hypertension is caused by liver cirrhosis and other causes, which can result in complications such as hypersplenism, fundic esophageal varices, and ascites. By treating portal vein shunt, the portal pressure will be reduced to normal level, which will improve hypersplenism and fundic esophageal varices, and will also reduce the production of ascites and facilitate the absorption of ascites. There are many surgical methods of portal vein bypass, and the appropriate surgical method should be chosen according to the severity of the patient’s complications in order to achieve a better treatment result.