Emerging and re-emerging viral diseases shared between wildlife and domestic animals are continually spreading to new geographic locations, influenced by human activities and environmental change. Canine distemper (CD) is probably one of the best examples of a disease that has been proved to be capable of compromising the conservation of several wild carnivore species. In this article, we describe a case report of CD in a grey wolf (Canis lupus) in Iran. A grey wolf was found in Fars Province close to Bamou national park. Clinical signs were characterized by neurologic signs, muscle twitching, hyperkeratosis of the footpads and nose and keratoconjunctivitis sicca. After the death of the animal, samples were taken from different organs and sent to collaborator laboratory of Fars Provincial Office of Veterinary Organization. RT-PCR assays confirmed canine distemper virus in the grey wolf. This is the first documented report of canine distemper virus in wild species from Fars Province of Iran.