About 20% of OPA1 mutation carriers have complicated forms of dominant optic atrophy associating extra-ocular features. Reviewing the files of 327 patients with an OPA1 mutation, we found 21 deaf patients (6.4%). In 10 patients deafness was detected under age 20, in 3 patients over age 20 and in 8 patients the age of onset was unknown. The severity of deafness ranged from mild and moderate. Audiological tests supported the diagnosis of auditory neuropathy in 8 cases. Seven different OPA1 mutations were identified in deaf patients. Three mutations, p.Arg445His, p.Gly401Asp and p.Leu243*, have been previously reported in patients with deafness. Two mutations, p.Val291_Phe328del and p.Ile463_Phe464dup, have been reported in patients with DOA without deafness. Finally, two novel OPA1 mutations, p.Arg437Glu and p.Ala357Leufs*4 were found. In the majority of patients with DOA and deafness, visual impairment occurred during the first decade while deafness appeared later. However, in 54% of patients deafness started prior to visual abnormalities. These observations suggest that audition should be carefully tested, including a specific search for auditory neuropahy in OPA1 mutation carriers.