To investigate ophthalmologic manifestations in children with definitive oxidative phosphorylation disorders, a retrospective review was conducted of clinical and laboratory records of all such pediatric patients (n = 103) diagnosed and treated at one center between 1983 and 2006. All were residents of Victoria, Australia. Nystagmus or roving eye movements were the most common ophthalmologic manifestations as a presenting symptom of disease (13/20) and were the sole manifestation at presentation in 10/13 patients. Divergent strabismus was a presenting symptom in 5/20 patients and was the sole manifestation at presentation in 3/20 patients. Abnormal eye movements were noted in 6 patients and strabismus was noted in 4 patients with Leigh's or Leigh-like disease; in 9 of these 10 patients, Leigh's disease was the result of complex I deficiency. Altogether, ophthalmologic manifestations were noted at presentation in 12/35 patients with complex I deficiency. External ophthalmoplegia in conjunction with ptosis was the presenting symptom in 3/20 patients, all with Kearns-Sayers syndrome. Patients suspected of having oxidative phosphorylation disorders should be referred for ophthalmologic examination. Prospective studies are needed for a comprehensive elucidation of the ophthalmologic findings in these disorders.