Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal-recessive disease associated with multiple deletions of mitochondrial DNA in skeletal muscle. MNGIE is a multisystem syndrome affecting muscle, peripheral, and central nervous systems and the gastrointestinal tract. A 25-year-old man is presented with 3 years history of right sided trigeminal neuralgia. He has been diagnosed as MNGIE based on clinical, neurophysiological and pathological findings. He had also received medical therapy and two radiofrequency thermocoagulations for the treatment of trigeminal neuralgia. Gamma Knife radiosurgery was performed and resulted in partial relief. To our knowledge, this is the first case in the literature of MNGIE with trigeminal neuralgia. An analogy is suggested between multiple sclerosis and MNGIE as a cause for trigeminal neuralgia in this patient. (c) 2004 Elsevier Ltd. All rights reserved.