ABSTRACT. This study aimed to isolate mesenchymal stem cells from bone mesenchymal stem cells (BMSCs), determine their therapeutic potential for treating rats with acute liver failure (ALF), further explore the factors that induce liver failure mechanisms, and elucidate the role of bone marrow stem cell therapy and BMSCs on liver homing. We found that differentiation potential was present in BMSCs expressing high levels of CD29 and CD90. These cells improved liver functioning in vivo after transplantation into rat livers with D-galactosamine damage, as evidenced by the levels of alanine aminotransferase and aspartate aminotransferase returning to normal (low levels) in recipient ALF rats. A significant improvement in the liver functional test and histological findings was observed in the Stem cells and acute liver failure transplantation group after 120 and 168 h of transplantation (P < 0.05). Histological data revealed that hepatocyte cell apoptosis was lower in the transplantation group compared to the control groups (P < 0.05), and that the transplantation of BMSCs reduced liver inflammation, decreased hepatic denaturation and necrosis, and promoted liver regeneration. These ameliorations were not recorded in the control groups. The results of in situ hybridization, immunofluorescence staining, and Western blot confirmed the presence of transplanted BMSCs in recipient rat livers. Stromal cell derived factor-1 alpha and vascular endothelial growth factor were significantly upregulated after the intraportal transplantation of BMSCs, with significantly higher levels being found in the portal vein and the tail vein groups (P < 0.05). In conclusion, BMSCs have a therapeutic effect against ALF rats, evoke endogenous repair mechanisms in the liver, and may represent a novel form of therapeutic intervention for the disease. Furthermore, intraportal transplantation serves as a more effective pathway compared to tail vein transplantation.