Hepatic ischemia-reperfusion (I/R) is associated with hepatocellular injury and distant organ dysfunction. Previous studies have demonstrated that a high-fat diet enriched with polyunsaturated fatty acids (PUFAs-w-3) has a protective effect on the liver, causing only mild liver steatosis. Aim: To evaluate the effect of a high-fat diet enriched with PUFAs (fish oil) on hepatic and pulmonary disturbances associated with hepatic ischemia-reperfusion injury. Methods: Thirty-one Wistar rats were divided in 2 groups: Group I (n=17): rats with fatty liver induced by high-fat diet enriched with PUFAs-w-3 for 4 weeks and Group II (n=14): received standard diet. Ten rats of group I and seven of group II were submitted to I/R. Hepatic mitochondrial oxidation and phosphorylation were measured polarographically by determining oxygen consumption without ADP (basal respiration, S4), and in the presence of ADP (activated respiration, S3). Serum aminotransferases (AST, ALT) were determined, and the study of hepatic tissue histology was carried out. The evaluation of the pulmonary lesions was done using the Evans blue test and the tissular determination of mieloperoxidade. Results: In the animals with fatty diet it was observed mild liver steatosis in the periportal zone, compared to group with a standard diet. Comparing the groups submitted to I/R, there was an increase in state 3 respiration (88.38±15.01 vs. 26.33±7.50), in the respiration control rate (2.86±0.59 vs. 1.55±0.,36), and the ADP/O ratio (1.72±0.18 vs. 1.21±0.16) in the group with a high-fat enriched with PUFAs-w-3 diet in relation of group II, with a standard diet (p<0.05). The PUFAs-w-3 enriched diet group had also lower levels of aminotransferases (AST:1087±775 vs. 6607±806; ALT: 1333±892 vs. 7132±1102) and the histological findings were significantly less intense (p<0.05). The pulmonary lesion didn’t show difference between the groups. Conclusion: The results suggest that a high-fat diet enriched with polyunsaturated fat (w-3) may have a protective effect in hepatic ischemia-reperfusion injury, probably due to PUFAs-w-3 capacity to reduce inflammatory response and the production of reactive oxygen species in the liver.