Hepatic veno-occlusive disease, which was observed in a patient with hepatic coma, was examined by scanning electron microscopy (SEM), and correlated with its histology. Postmortem examination disclosed microscopic occlusion of the centrilobular and sublobular veins in the liver. These veins were occluded, partially or completely, by intimal and medial thickening of their walls due to proliferation of collagen and reticulin fibers. In addition to venous obliteration, which had not been demonstrated by other techniques, frequent occlusion of the sinusoidal opening into the central veins was observed by SEM. The size and distribution of the openings were irregular in comparison with those in normal controls. There was no evidence of fibrin thrombus formation in the veins. This case exemplified the usefulness of the application of SEM to autopsy material.