【Abstract】Objective To study the effect of bioartificial liver on severe hepatitis with the plasma exchanged from the patient with severe hepatitis and the role of exchanged plasma in the research of bioartificial liver as a model of servere hepatitis. Methods The plasma was aseptically collected from the patient with severe hepatitis during the treatment of plasma exchange operation. The effect of bioartificial liver with porcine hepatocytes on the biochemical changes and biotransformation of aminophylline was investigated by the circulating of the plasma in vitro. Results The levels of total serum bilirubin, r-glutamyl transpeptidase, cholinesterase, glucose, cholesterol, serum glycoprotein in the plasma from the patient with severe hepatitis were lowed and the levels of total protein, albumin, triglycerides were elevated after the treatment of bioartificial liver by circulating in vitro. The content of aminophylline was decreased rapidly after the treatment. Conclusion The bioartificial liver with porcine hepatocytes could cause the metabolic changes of sugar, lipids and protein and drug biotransformation in the exchanged plasma. And the exchanged plasma from the patient with severe hepatitis is sensitive to the treatment of bioartificial liver as a model of severe hepatitis in vitro. It is valuable to the study of the bioartificial liver on severe hepatitis.