Two different experiments were carried out in order to investigate the influence of feeding n-3 and n-6 PUFA enriched diets on the relationship of lipid peroxidation and antioxidant status including fatty acid composition and quality in longissimus muscle from bulls. The lipid peroxidation extent in muscle depended on the antioxidant status offered by each diet. Antioxidant capacity of muscle was no affected by the diet using TEAC and FRAP assay. There was a combined effect of n-3 PUFA enriched diet and feeding restriction lipid peroxidation, and tenderness of longissimus muscle.