We describe cholestasis as a result of bile duct abnormalities in 8 children with portal vein obstruction. In a clinical, biochemical and radiological investigation of 121 children with cavernous transformation of the portal vein seen between 1986 and 2000, 8 presented with jaundice, pruritus, and/or raised serum aminotransferases and/or gamma glutamyl transpeptidase (gamma GT) activities. Each displayed dilation and narrowing of intra- and/or extrahepatic bile ducts. Surgical decompression of the portal system (portal-systemic or Rex anastomosis) resulted in the regression of the signs of cholestasis in all children. We conclude that children with portal vein obstruction may exhibit clinically significant cholestasis as a result of external compression of the bile duct by the cavernoma.