A 59-year-old man was diagnosed to have idiopathic myelofibrosis (IMF) in November 2001. In April 2004, massive ascites and esophageal varices were found. IMF was considered to be the cause of portal hypertension (ascites and esophageal varices). Since ascites tend to be intractable with diuretic drugs, a transjugular intrahepatic portosystemic shunt (TIPS) was inserted in May 2004. Before TIPS, his waist measured 98 cm. On day 74 after TIPS, his waist measured 68 cm as a result of the administration of diuretic drugs alone. He eventually died due to hepatic failure on day 168 after TIPS. The autopsy findings suggest that sinusoidal fibrosis caused portal hypertension.