Four consecutive patients, three with fulminant hepatic failure and one with a severe relapse of serum hepatitis, who showed evidence of intravascular coagulation, were treated intensively with heparin and fresh frozen plasma. Rapid correction of the coagulation disturbance was achieved, and all four patients recovered completely. The necessity for starting such treatment early in the course of the disease and before the onset of major gastrointestinal bleeding is stressed, and it is suggested that intravascular coagulation may act as an intermediary in the pathogenesis of the hepatic necrosis.