Abstract: Objective To explore the therapeutic effect of plasma exchange in the treatment of patients with acute-on-chronic liver failure（ACLF）. Methods 50 patients with ACLF were treated with plasma exchange on the basis of routine treatment. The hepatic function，coagulation tests and improvements of clinical symptoms were compared. Results After treatment，the patients' total bilirubin，alanine aminotransferase，aspartate aminotransferase，prothrombin time decreased（P<0.01），prothrombin time activity（PTA）increased（P<0.01），and clinical symptoms improved. 32 cases（64.0%）out of the 50 patients survived. The effective rates of early，middle and late stage of ACLF patients were 95.8％，43.8％ and 20.0％，respectively. Conclusions Plasma exchange is safe and effective in treatment of patients with ACLF.

Key words: Acute-on-chronic liver failure, Plasma exchange, Therapeutic effect