This study investigated the effects of ${alpha}$-lipoic acid (ALA) supplementation on the malondialdehyde (MDA) contents and superoxide dismutase (SOD) protein expression in rat skeletal muscles under non-exercising condition. Fourteen Sprague-Dawley male rats at the age of 6 weeks were randomly divided into 2 groups CS, (normal diet group, n=7) and AS (0.5% ALA supplemented diet group, n=7), and keep non-exercising condition for 4 weeks. The muscle MDA concentration of the AS group was significantly lower than that of the CS group in the both soleus and extensor digitorum longus muscles. The expressions of Cu/Zn-SOD and Mn-SOD proteins in the soleus muscle were significantly higher in the AS group than that in the CS group. From these results, ALA supplementation under non-exercising condition had a role in increasing of antioxidant enzymes in skeletal muscle types of rats.