Five patients with obstruction of the hepatic portion of the inferior vena cava diagnosed by digital subtraction inferior vena cavography were reported. All of these patients, aged from 38 to 52, were female who had never used the oral contraceptives. Main collateral pathway of these patients was the central channels through ascending lumbar veins, internal and external vertebral plexuses, azygos-hemiazygos complex, and inferior vena cava itself above the obstructed segment.