A device of extrahepatic portacaval shunt is introduced. This device is composed of the daughter and parent magnets and the vascular interventional operation equipment. It is based on the principle of magnetic compression technology, through the intervention approach the daughter and mother magnet are moved to the portal vein and inferior vena cava, respectively. Then the two magnets attract and compress the vessel walls of portal vein and inferior vena cava. Two weeks later, the magnets are detached from the vessel wall with a RUPS-set and the portacaval shunt is established. It is mainly used for the treatment of portal hypertension. It belongs to the interventional operation, there is no any foreign body remaining after the portacaval shunt is established, which can maintain long-term patency. Futhermore the portacaval shunt will not be expanded, therefore it can significantly reduce the incidence of hepatic encephalopathy.