Objective To observe the clinical effect of plasma exchange（PE），double plasma molecular adsorption system（DPMAS）and molecular adsorption recycling system（MARS）in the treatment of acute-onchronic liver failure，and to find the best way for the treatment of liver failure. Methods From January 2017 to December 2018，66 patients with acute-on-chronic liver failure who underwent liver transplantation in our hospital were analyzed retrospectively. According to different treatment methods，they were divided into PE group（23 cases）， DPMAS group（23 cases）and MARS group（20 cases）. The clinical data of all patients before and after treatment were collected and analyzed. Results The effective rate of MARS group was 90.0%，higher than that of PE group and DPMAS group（52.2% and 56.5%）. The difference was statistically significant（P ＜ 0.05）. There were significant differences in white blood cell，hemoglobin and platelet counts between the three groups before and after treatment （P ＜ 0.05）. In PE group，international normalized ratio（INR）and prothrombin activity（PTA）were significantly improved after treatment（P ＜ 0.05）. The liver function indexes of the three groups were improved after treatment， and MARS group was the most obvious（P ＜ 0.05）. Conclusion There are advantages and disadvantages in the three kinds of artificial liver treatment modes，of which MARS is the best one. The treatment mode should be selected reasonably according to the patients' condition in clinical work.