Objective To evaluate the long-term prognosis and safety of ABO-incompatible (ABO-I) liver transplantation on type-O patients with acute severe liver disease,analyze and compare the effects and main complications between different donor blood types,and investigate corresponding treatment measures.Methods The clinical data of 65 cases of emergency orthotopic liver transplantation (OLT) for type-O patients with acute severe liver disease from January 2014 to January 2017,including 41 cases of ABO-compatible (ABO-C) OLT and 24 cases of ABO-incompatible OLT (7 with type-A donor,9 with type-B donor,and 8 with type-AB donor) were retrospective analyzed.Results The model for end-stage liver disease (MELD) score in the ABO-incompatible group was 32.5±5.5,significantly higher in the ABO-compatible group (23.3±8.9) (P=0.001).The data of the other perioperative factors showed no statistically significant difference between two groups.The cumulative survival rate in the ABO-compatible group was 87.8 % (36/41),not significantly different from that in the ABO-incompatible group [87.5% (21/24),P=0.924].The 57 cases who had survived after perioperative period were followed up for 4-37 months (mean 18 months).Significantly higher incidence of hepatic artery and biliary complications was found in ABO-incompatible group (P=0.005,and P<0.001,respectively).The incidence of hepatic artery complication and biliary complication in ABO-incompatible group was 29.2% (7/24) and 37.5% (9/24),and that in ABO-compatible group was 4.9% (2/41) and 0 (0/41),respectively.The rate of acute rejection in the ABO-incompatible group and ABO-compatible group was 9.8% (4/41) and 4.2% (1/24) (P=0.463).The infection rate in the ABO-compatible group and ABO-incompatible group was 24.3% (10/41) and 29.2%(7/24),respectively (P=0.598).Conclusion The different donor blood types including ABO-compatible and ABO-incompatible liver transplantation program on type-O patients with acute severe liver disease have a favorable outcome.The long-term cumulative survival rate between two groups shows no significant difference.With the help of effective immunosuppression and intensive perioperative management,ABO-incompatible liver transplantation is an acceptable option to cure type-O patients with acute liver failure in emergency.The incidence of hepatic artery and biliary complications was lower in ABO-compatible group than in ABO-incompatible group.For the type-O patients with ABO-incompatible liver transplantation,the use of rituximab and plasma exchange to decrease the antibody titers of recipients is essential to prevent and cure the hepatic artery and biliary complications.