Objective : This study on Sipimikwanjung-tang was undertaken to evaluate its antioxidant capacities and antiperoxidation activities in rat liver tissues. Sipimikwanjung-tang which has been one of the prescriptions in sasang constitutional medicine is usually applied for the therapy of various liver diseases. It is elucidated that Sipimikwanjung-tang has antioxidants on liver tissue of rat and the cytotoxic effects on human hepatoblastoma Hep G2 cells. Methods: Sipimikwanjung-tang extract in antioxidant effects of Hep G2 cells is evaluated by MTT assay, DAPI staining, DNA fragmentation assays and FACS can analysis. Results: Sipimikwanjung-tang induced apoptosis in Hep G2 cells, and induced G1 and G2M arrest of the cell cycle as well as a significant increase in PARP and caspase-3 activity. It induced an increase in $H_2O_2$ generation and the subsequent $NF-{kappa}B$ activation and also induced cell apoptosis through the caspase-3-dependent pathways in the low concentration of Sipimikwanjung-tang extracts. However, the high dose of Sipimikwanjung-tang extract in Hep G2 cells inhibited $TGF-{eta}l-induced$ apoptosis via increase in cellular $H_2O_2$, formation and $NF-{kappa}B$ activation in human hepatoblastoma Hep G2 cells. Conclusion: From this study, the possibility that Sipimikwanjung-tang extracts apply to antioxidant and apoptotic treatment of disease is revealed.