A case of complete inferior vena cava obstruction with resultant unusual collateral circulation is reported. On venographic examination of a 50 year old male who showed complex superficial colateral channels on right sidetrunk, complete obstruction of the middle portion of inferior vena cava was demonstrated, and thereafter maincolateral flow was just served with inferior phrenic, lumbar, and vertebral venous plexus veins. Systemic venousblood from the above collateral channels was mainly connected not with the usual azygos-hemiazygos system to the superior vena cava but with the left cardiophrenic or superior phrenic vein which was proven to present itself asscalloped nodular densitis along the left cardiac border on the plain chest films. Brief comments on thecollateral circulation is described with review of literaturs.