Antibodies to Encephalitozoon cuniculi were found in wild arctic foxes (Alopex lagopus), feral mink (Mustela vison), wood mice (Apodemus sylvaticus) and house mice (Mus musculus) in Iceland. Animals with antibodies were found throughout the country. No lesions attributable to encephalitozoonosis were found in adult animals necropsied. However, one arctic fox cub with a neurological disorder had pathological and serological evidence of encephalitozoonosis.