We describe 10 patients with long-standing portal hypertension and calcifications in the splenoportal and mesenteric venous systems or collateral vessels. The patients were examined with abdominal plain films (n = 10), sonography (n = 10), and CT (n = 9). Calcium was seen on CT scans in nine cases, on sonograms in seven, and on abdominal plain films in five. Calcifications appeared to be located in the wall of the vein in all cases. Sites of detection included the main portal, splenic, superior mesenteric, coronary, and peripancreatic veins. CT was more sensitive than sonography, and both were more sensitive than plain films, in showing portal venous calcification. Detection of such calcifications may influence surgical or percutaneous therapy of portal hypertension.