Background: The cause of multiple sclerosis (MS) is unknown, although it is widely accepted that environmental factors act in concert with a genetic susceptibility. Objective: To evaluate the effect of 3 months supplementation of antioxidants vitamins (ascorbic acid (vitamin C) and alphatocopherol (vitamin E)) on the oxidant / antioxidant status and on the clinical course in patients with relapsing remitting MS (RRMS) and to compare with the placebo therapy and healthy subjects as a control. Patients & Methods: This is a non randomized single blinded clinical trial was conducted on a total number of 60 patients (24 males and 36 females) with age ranged between 15-54 years, diagnosed to have relapsing-remitting multiple sclerosis (RRMS) and were registered at Neurology Outpatients Department in Ibn Sina Teaching Hospital in Mosul City / Iraq and receiving subcutaneous β- interferon, in the period from 1st of February 2012 to the 1st of July 2012. The patients were divided into two groups: First group included thirty patients, started to receive the antioxidant vitamins therapy with vitamin C and vitamin E, for 3 months duration. The second group included thirty patients, were kept on a placebo therapy for 3 months duration. Another thirty apparently healthy individuals, non smokers, matched for age and sex with the patients, considered as the control group. Approximately 5ml of venous blood was drawn from the two MS patient groups prior to start taking the antioxidant or placebo therapies and after 3 months of therapies and collected once from healthy control subjects. The sera obtained from the blood samples of the precipitant in this study used for measuring total antioxidant status (TAS) level using a commercial kit while malondialdehyde (MDA) level were measured by using a manually prepared reagent. The clinical course of MS patients were assessed using expanded disability status score (EDSS). Results: There were significantly higher level but a significant lowe