Aims: The aim of this study was to investigate the antioxidant effects of L-carnitine on the oxidative stress parameters in oophorectomized rats. Methods: Twenty-four female albino Wistar rats were used. Rats were divided into four groups: laparotomy-only (LOSALINE) group, oophorectomy plus L-carnitine 100 mg/kg/day (OXL100) group, oophorectomy plus L-carnitine 500 mg/kg/day (OXL500) group, and oophorectomy-only (OXSALINE) group. Experimental protocol was started on day 21 post-castration. Various dosage forms of L-carnitine or isotonic saline were administered intraperitoneally for 14 consecutive days. Nitric oxide (NO), malondialdehyde (MDA), total antioxidant status (TAS), total oxidative stress (TOS) and oxidative stress index (OSI) were evaluated in the tissues including kidney, liver and heart, and sera. Result(s): In the heart tissue samples, there was no difference in the levels of NO, OSI and TOS between the groups. However, MDA levels in OXSALINE group were significantly higher than OXL500 group. On the other hand, there was no statistically significant differences between the groups in terms of levels of NO, MDA, TAS, TOS and OSI in liver, kidney and sera samples. Conclusion(s): Levels of MDA in the heart tissue were significantly higher in OXSALINE group compared to OXL500 group. Thus, it may be suggested that L-carnitine reduces oxidative stress at least in the heart of oophorectomized rats. (C) 2016 Alexandria University Faculty of Medicine. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).