Hepatic veno-occlusive disease (VOD) is a typical complication occurring soon after allogeneic hematopoietic stem cell transplantation (HST), characterized by jaundice, painful liver enlargement, and weight gain due to fluid retention. The study reported here concerns a patient with VOD after allogeneic HST. Hemodynamic evaluation using ultrasonography revealed reversed portal venous flow before elevation of serum bilirubin, in addition to gallbladder wall thickening, ascites, and hepatomegaly. Quantitative evaluation using abdominal ultrasonography showed improvement in the reversed portal venous flow before the peaking of the serum bilirubin level and coagulopathy. This analysis was useful for both early diagnosis and clinical follow-up of VOD.