ABSTRACT Two female patients, aged 23 and 25 years-old diagnosed with Familial Mediterranean fever (FMF) were presented with ataxia and headache. Multiple sclerosis plaques were detected in their spinal and cranial MRI and diagnosis of multiple sclerosis was established. Genetic analysis demonstrated M694 V mutation (one homozygous and the other heterozygous) in both of the patients. Although it is quite rare, coexistence of familial Mediterranean fever and multiple sclerosis should be kept in the mind.