As shown in previous study dietary n-3 PUFAs suppress the connective tissue proliferation in the rat liver wound with concurrent high level of lipid peroxidation. In the present study influence of alpha-lipoic acid as a natural antioxidant on the n-3 fatty acid induced effects has been investigated. Animals were given commercial rat pellet diet (control group, n=6) or diets enriched with 10% of sunflower oil (source of n-6 PUFAs, n=6) or 10% of fish oil (source of n-3 PUFAs, n=6) for 8 weeks. Alpha-lipoic acid was added to the same diets at the calculation of 30 mg per rat for 10 days before the liver thermic wound was induced. Lipoic acid treatment was continued after wound infliction for 6 days, then in the liver wound the proliferation of the connective tissue, the lipid peroxidation and peroxidizability, and the content of prostaglandins E 2 and F 2 α was estimated. Lipoic acid prevented n-3 fatty acid induced suppression of the connective tissue proliferation, avoided peroxidation of lipids, reduced peroxidizability of lipids and modulated the decrease of PGE 2 and PGF 2 α . The results indicate that dietary alpha-lipoic acid may prevent n-3 fatty acid induced adverse effects.