The purpose of this study was to clarify the effect of orthotopic liver transplantation on hypersplenism. In a I-year period from July 1, 1986 to June 30,1987 adult patients underwent 233 orthotopic liver transplantations. Of the 58 patients with hypersplenism who were analyzed in this study, hypersplenism was more commonly associated with postuecrotic cirrhosis than other kinds of liver disease (55.3% (47/85) "S. 14.5% (11/76); p < 0.0(1». Postoperative platelet counts were statistically higher than preoperative values (p < 0.05). The latest platelet counts were more than lOO,OOO/mm 3 in 53 patients (91.4%). Of the eight patients whose preoperative and postoperative spleen volumes could be compared, all showed the reduction in the spleen size (p < 0.02). We conclude that orthotopic liver transplantation, wbich is a radical surgical procedure for portal hypertension, reverses hypersplenism.with liver cirrhosis, which· commonly pre~ents itself as splenomegaly with hematologic disorders, i.e., leukopenia, thrombocytopenia, and anemia. 1 The incidence of hypersplenism among cirrhotics varies from 15% to 70%,1 and splenectomy is known to relieve the hematologic disorders associated with this clinical entity.2-4 Passive congestion of the spleen due to portal hypertension is thought to cause the splenomegaly, which results in the sequestration and the destruction of the blood elements. 5 ,6 Although portacaval and distal splenorenal shunts are known to reduce the splenic vein pressure, the effect of these shunts on hypersplenism remains