ABSTRACT PURPOSE: To investigate the effect of silymarin on oxidative stress and hepatic injury induced by obstructive jaundice in an experimental model. METHODS: Thirty Wistar-Albino type female rats were divided into 3 groups each including 10 rats. Only laparotomy was performed in group 1. Bile duct ligation was performed in group 2. In group 3, bile duct ligation was performed and orogastic silymarin 300 mg/kg/day dose was given for seven days. At the end of seven days, rats were sacrificed. The blood and liver tissue samples were taken to be examined biochemically and histopathologically. RESULTS: The plasma and liver levels of malondialdehyde were significantly lower in silymarin group than in the bile duct ligated group. Although liver levels of GSH were significantly higher in silymarin group than in the bile duct ligated group, there was no significant difference between the plasma GSH levels of these groups. In silymarin group; the enlargement of hepatocytes, dilatation of canaliculi and the edema were regressed. CONCLUSION: Silymarin diminished the harmful effects of obstructive jaundice on liver.