In this study, antioxidant enzyme activities and the histopathologic structure of rats were examined in order to determine the injury that occurs in the liver after renal I/R. There were 5 groups: Group I (Control), Group II (Right nephrectomy + untreated control), Group III (Right nephrectomy + I/R and olive oil treated), Group IV (Right nephrectomy + I/R and 25 mg.kg(-1) carvacrol + olive oil treated group), Group V (Right nephrectomy + I/R and 50 mg.kg(-1) carvacrol + olive oil treated group). 45 min of Ischemia and 24 h of Reperfusion were applied to all groups of rats except Group I. Liver CAT, SOD, Gpx enzyme activity and AST, ALT levels were evaluated at the end of the experiment and values close to the control group were obtained for rats to which 50 mg.kg(-1) of carvacrol was administered. Significant injuries such as cellular degenerative changes, sinusoidal congestion and cytoplasmic vacuolation were determined for Group II in light microscopic examinations of liver sections. 25 mg.kg(-1) of carvacrol dose was found to be protective in Group IV.