PURPOSE: The purpose of this study was to investigate the effects of treadmill exercise on blood components and antioxidant system in hyperlipidemic rats. METHODS: Three weeks old male rats were randomly assigned into General diet(GD, n=10), High fat Diet(HD, n=10), and High fat diet+Treadmill exercise(HDT, n=10) groups. Treadmill exercise consisted of the treadmill running 5 times per week during 6 weeks(30 min/time for first 3 weeks and 60 min/time the other 3 weeks). RESULTS: The levels of triglyceride and total cholesterol were increased in HD group compared with GD group, and recovered to level of GD group by treadmill exercise(p<.05). Plasma glucose and insulin concentrations were increased in HD group compared with GD group, and recovered to level of GD group by treadmill exercise(p<.05). Glutathione(GSH) and glutathione reductase(GRD) concentrations were decreased in HD group compared with GD group, and these decreases returned to the level of GD group by treadmill exercise(p<.05). Xanthine oxidase(XO) and malondialdehyyde (MDA) concentrations were increased in HD group compared with GD group, and these increases retuned to the level of GD group by treadmill exercise(p<.05). CONCLUSION: This study showed that treadmill exercise application were effective treatment strategy on hyperlipidemia. Therefore, it could be considered as a treatment method in the patients with hyperlipidemia disease. Treadmill exercise, Hyperlipidemia, Blood components.