A 68-year-old male with hypereosinophilic syndrome developed acute hepatic veno-occlusive disease. The diagnosis of veno-occlusive disease was made mainly based on clinical symptoms and hepatic phlebography. Although veno-occlusive disease caused hepatic failure complicated with massive ascites, consciousness disturbance and coagulation abnormality, all of these manifestations subsided shortly after the start of corticosteroid therapy for hypereosinophilic syndrome. Since eosinophils cause direct tissue damage and local hypercoagulation, it is suggested that hypereosinophilia may be actively involved in the development of hepatic veno-occlusive disease in the course of the disease state.