Multiple sclerosis (MS) is an inflammatory demyelinating disease which the exact etiology is still are far to be clear. Reasons for this autoimmune disease are unknown origin. The aim of present study was to evaluate serum levels of selenium in patient with MS compare to healthy subjects. A total of 46 subjects were enrolled in the study, Sera of 23 MS cases and 23 healthy normal cohorts as control group were obtained. Atomic absorption spectrophotometer was employed for estimating serum selenium level. Serum
selenium levels were significantly lower in MS than in control cohorts (60.87±13 compared with 85.74±12, P-value < 0.0001). Serum selenium levels may thus be a marker of MS; the decreasing levels of serum selenium may be host defense strategies of body.