The relationship between idiopathic portal hypertension (IPH) and extrahepatic portal vein thrombosis (EPVT) remains controversial. In a retrospective study, we compared the clinical features of 21 patients with IPH, 27 with EPVT, and 38 with liver cirrhosis (LC). The variables with statistical difference between IPH and EPVT were age (38 +/- 17 years versus 29 +/- 14, respectively; p < 0.05), and 5-year survival (72 versus 92%, respectively; p < 0.05). The other clinical and laboratory variables had similar distribution in IPH and EPVT. LC patients were older than those in the other groups (48 +/- 13 years, p < 0.05), and had a poorer 5-year survival (60%, p < 0.05). Furthermore, LC patients had clinical features of liver failure in a higher proportion than the other groups did. The results suggest that IPH, EPVT, and LC are separate clinical entities.