Abstract： Objective:To assess the efficacy and safety of reformed typeTECAI bioartificial liver support system(BALSS) on treatment of acute liver failure(ALF)in a canine model induced by acetaminophen. Methods:The ALF canine model by multiple subcutaneous injections of acetaminophen were replicated. The primary hepatocytes were separated from the swine and cultured within the BALSS. The ALF model was treated with BALSS for six hours, the changes in physiological,biochemical and histological parameters were observed before and after the treatment ,and compared them with that after drugs treatment and control groups. Results:The ALF canine model was developed 48 hours after administrate of acetaminophen, the successful rate of model was 63.16%. Using our modified enzymatic digestion method, the yield of hepatocytes was (0.83.0)×1010 from per swine with high viability. Type TECAI BALSS treatment resulted in beneficial effects with decrease in plasma NH3, alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP) levels decreased,and the ratio of branchchain amino acid to aromatic amino acid(BCAA/AAA) increased. The pathological changes of the liver were repaired,and the animals with ALF could live longer than 30 days. The conditions of ALF models after the coventional treatment and control groups deteriorated,and they died within 14.8360.00 hours. Conclusions:This type of BALSS is rapid,safe and efficacious in providing liver support in the ALF canine model.The efficacy of BALSS is superior to the routine drugs treatment,and it would hopefully be a new method in the treatment of ALF.