Abstract: To investigate the effects of S-adenosylmethionine (SAM) on ethanol-induced liver injury in rats.48 female SD rats were randomly divided into 4 groups, control, model, low dose and high dose SAM groups.Except control group, all rats were fed with high fat-containing diet plus ethanol and fish oil gavage for 8 weeks.SAM were administered by intraperitioneal injection after 4 weeks exposure of ethanol.Plasma total homocysteine (tHcy) , serum aminotransferase activity (ALT) , total cholesterol (TC) , triglyceride (TG) , TNF-α, TGF-β level, and liver malondialdehyde (MDA) , and glutathione (GSH) contents were assayed, Liver histology was also examined.Compared with control group, model group rats developed markedly liver damage, accompanied with an increased level of tHcy, ALT, TC, TG, TNF-α, TGF-β and MDA, and decreased level of GSH (P<0.01) .In treatment groups, SAM significantly protected from liver injury, reduced ALT, TC, TG, MDA, TNF-α and TGF-β levels (P<0.05) , and enhandced GSH level (p<0.01) .But plasma tHcy levels was not affected significantly (P>0.05) .there was no statistical difference in above parameters between the two dose groups (P>0.05) .SAM prevents liver from alcohol-induced injury in rats by reducing liver lipid peroxidation, anti-inflammation and anti-hyperplasia.SAM does not affect the plasma tHcy level.