Large portal-systemic shunts in cirrhotic patients often cause recurrent hepatic encephalopathy and might promote liver dysfunction because of the reduced portal blood flow. We report a case of liver cirrhosis in which hepatic encephalopathy disappeared and liver function improved together with an increase of hepatopetal portal blood flow and liver volume after shunt resection. A 70-year-old woman with liver cirrhosis was admitted because of recurrent disorientation. Serum ammonia levels ranged from 174 to 321 micrograms/dL. Computed tomography demonstrated an atrophic liver and a large shunt. Portography disclosed that this shunt originated from the superior mesenteric vein and flowed into the inferior vena cava, common iliac vein and ovarian vein. Portal blood flow was poor because of the deviation into this shunt. After the surgical resection of the shunt, ammonia levels were normalized and hepatic encephalopathy no longer occurred. Portography and computed tomography after surgery demonstrated that hepatopetal portal blood flow evidently improved and the liver volume increased (before 369; after 574 cm3). Two years after surgery, hepaplastin test and serum albumin level improved from 41 to 76% and from 2.7 to 3.4 g/dL, respectively. This case supports the effectiveness of shunt resection for hepatic encephalopathy and the deteriorated liver function in cirrhotic patients with large portal-systemic shunt.