We compared the clinical efficacy of high-flow dialysate continuous hemodiafiltration (HFCHDF) performed as artificial liver support (ALS) in fulminant hepatic failure (FHF) with those of conventional ALS techniques. Ninety patients were divided into non-HFCHDF and HFCHDF groups. Rate of recovery from coma was significantly higher in the HFCHDF group (70.2%) than in the non-HFCHDF group (44.2%) (p<0.01). The excellent recovery rate from coma achieved in patients with FHF by HFCHDF may be due to its enhanced capacity for liver support enabling efficient removal of substances causing hepatic coma from blood. HFCHDF should thus be useful for ALS.