Syh-Mo-Yin (SMY), Guizhi-Fuling-Wan (GFW), Shieh-Qing-Wan (SQW) and Syh-Nih-San (SNS) are prescriptions of Traditional Chinese Medicine (TCM) for liver disease. The effects of these four prescriptions against experimental liver injury induced by alpha-Naphthylisothiocyanate (ANIT) and carbon tetrachloride (CCl4) were studied. Rats treated with ANIT (100 mg/kg) exhibited elevations of serum total bilirubin (TBI), alkaline phosphatase (ALP), glutamate-oxalatetransaminase (sGOT) and glutamate-pyruvate-transminase (sGPT) as well as cholestasis and parenchymanecrosis. In rats receiving SMY, SQW and SNS treatment after ANIT challenged, the biochemical and morphological parameters of liver injury were significantly reduce. Elevated lipid peroxidation (LPO) level in liver tissue, associated with an increase in serum GOT and GPT level, was observed in CCl4-treated rats. Treatment with these four prescriptions on CCl4-induced liver injury rats showed a remarkable hepatoprotective effect. A significant decrease in peroxidative level suggested that these prescriptions have anti free radical properties.