Objective: Cyclophosphamide (CP) is among the most commonly used anti-cancer and immunosuppressant drugs. The efficacy of this agent often is limited by severe side effects and toxic conditions. The present experimental study was undertaken to determine whether L-carnitine (LCAR), as a potent antioxidant compound, could ameliorate CP-induced oxidative liver and intestinal injury. Material and Methods: Thirty-two Wistar rats were divided into four (control, CP, CP + LCAR and LCAR) groups each containing 8 rats. The antioxidant agent LCAR or saline was given to rats for 5 days after administration of a single dose of CP. On the sixth day, rats were sacrificed and liver and ileum tissue samples were obtained and stored to measure reduced glutathione (GSH) and malondialdehyde (MDA) levels, myeloperoxidase (MPO) and superoxide dismutase (SOD) activities. Results: CP decreased GSH level and SOD activity and increased MDA levels and MPO activity in the liver and intestinal tissue homogenates. These changes except intestinal SOD activity were significantly reversed by LCAR treatment. Although intestinal SOD activity increased with LCAR treatment compared to the CP group, this increase was not significant. Conclusion: Our results demonstrated that, LCAR could ameliorate the depletion of GSH and SOD activities and could reduce the activities of MPO and levels of MDA in rat liver and intestinal tissues; this makes it a potential prophylactic and preventive agent against CP-induced oxidative stress. In conclusion, these data indicate that LCAR may be of therapeutic use in preventing hepatotoxicity and intestinal injury in patients receiving chemotherapeutic agents.