Ascorbic acid (vitamin C) is a water-soluble micronutrient required for multiple biological functions. Ascorbic acid has been found to have a long history of use in traditional systems with antioxidant effects that can control the generation of free radicals. Free radical level was reported to be high in cancer cells. The objective of this study was to observe the effects of ascorbic acid (40mg/kg/BW/day for 12 weeks) on hematological and thiobarbituric acid-reactive substances in adult male rabbits. The effects of ascorbic acid on total erythrocyte counts (RBC), hemoglobin (Hb), packed cell volume (PCV), total leukocyte counts (WBC), mean cell volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), plasma glutathione-S-transferease (GST), acetylcholinesterase (AChE) and thiobarbituric acidreactive substances (TBARS) at end of 12-week of treatment. Treatment with Ascorbic acid caused significant (P<0.05) increase in RBC and WBC, while did not cause any changes in Hb, PCV, MCV, MCH, MCHC, the activity of GSH and AChE compared to control. (TBARS) was significantly (P<0.05) decreased compared with control group. The study concludes that adding a Vitamin C source with a meal can improve anemia situation and reduce free radicals in adult male rabbits over an extended period of time