Aim: To design the effective directed differentiation medium to differentiate bone marrow cells into hepatocyte-like cells. Methods: Bone marrow cells were cultured in the directed differentiation media including fibroblast growth factor-4 (FGF-4) and oncostatin M (OSM). Hepatocyte-like cells from directed differentia tion of bone marrow cells were identified through cell morphology, RNA expressions by reverse transcriptase-polymerase chain reaction (RT-PCR), protein expressions by Weste blot, and hepatocellular synthesis and metabolism functions by albumin ELISA, Periodic acid-Shiff staining and urea assay. Results:Some epithelial-like cells or polygonal cells appeared and increased in the course of the cell directed differentiation. Hepatocyte nucleur factor-3β (HNF-3β), albumin (ALB), cytokeratin 18 (CK18), transthyretin (TFR), glucose-6-phosphate (G6-Pase), and tyrosine aminotransferase (TAT) mRNA were expressed in the course of the directed differentiation. The directed differentiated cells on d 21 expressed HNF-3β, ALB, and CK18 proteins. The directed differentiated cells produced albumin and synthesized urea in a time-dependent manner. They could also synthesize glycogen. Conclusion: Our differentiation media, including FGF-4 and OSM, are effective to differentiate bone marrow cells into hepatocyte-like cells, which could be used for hepatocyte resources for bioartificial liver or hepatocyte transplantation.