Objective To establish a novel bioartificial liver (BAL) consisting of spheroids of porcine hepatocytes in a hollow-fiber bioreactor, and to perform an in vitro study on its metabolic effects on the serum from severe hepatitis B patients.Methods Hepatocytes were isolated from pup pigs and cultured as aggregate spheroids through rotation and vibration. Phase-contrast microscopy, transmission electron microscopy, and scanning electron microscopy were used for morphological detection of hepatocyte spheroids. The hepatocyte spheroids were then transferred into the shell of a polysulfone hollow-fiber bioreactor, creating a novel BAL. Diluted serum samples of severe hepatitis B patients were circulated for 3 hours each into the bioreactor, by using an extracorporeal circulatory system. Every half hour, including both before and after perfusion, serum samples were collected to assay total bilirubin (TBIL), total protein (TP), albumin (ALB), and globulin (GLB) concentrations in order to judge the metabolic effects of this novel BAL. Results Most hepatocytes had formed spheroids with high viability after 24 hours in culture. After 3 hours of perfusion, when compared with the control group, the serum concentration of TBIL in the treatment group decreased significantly (P