Clinically, idiopathic portal hypertension (IPH) is characterized by overt splenomegaly with pancytopenia, portal hypertension and relatively mild abnormalities in liver function tests. Although its etiology is still undetermined, the liver pathology is characterized by occlusive changes of the intrahepatic portal radicles, portal and periportal fibrosis, irregularly distributed parenchyma atrophies and absent of regeneration nodules. The disease is relatively benign and does not progress to cirrhosis. Differential diagnosis between IPH and liver cirrhosis is mandatory. We now report a case with histologically proven IPH, including clinical course, laboratory data, roentgenographic findings of hepatic venogram and celiac angiogram, hepatic hemodynamic features and intravariceal pressure of esophageal varix which has never been reported in Taiwan.